I just finished a modded WotC campaign and I'm trying to give feedback for some of the mods I used. For reference, it was a Beta Strike campaign on Veteran (Upped to Commander midway through). I used a slew of minor and quality of life mods, along with the following major ones:
-Richards Classes Redux (Plus LW Weapons)
-Point Based Not Created Equal
-A Better Advent
-Grimy's Loot
-Bio Troops/Beasts/Command
-Trainable Sparks + Metal Over Flesh
-MOCX

First off, really solid work. I have a number of criticisms, but on the whole your mod offers a solid alternative to the base classes and I'd be comfortable recommending it to someone looking to mix things up without going too overboard. On the whole, the classes definitely felt more powerful than vanilla but not ludicrously so.

Assault
This was undoubtedly my MVP class this playthrough. Losing stealth was a small price to pay for its upgrades over a standard Ranger. I went with a melee build and once it got going it was probably more deadly than several other soldiers combined. I happened to roll Hip Fire on my guy which synergized incredibly well with Run & Slice. Even with Beta Strike my guy was regularly taking out around half a pod on one turn. Lacerate ended up being pretty disappointing, mainly because I was already getting 50%+ critical chance with normal attacks. If I had rolled Reaper, then my guy would probably have crossed into the "ludicrous" side of things.

If you want to bring Lacerate in line with Reaper, I'd suggest some kind of whirlwind attack, similar to Ionic Strike. But, really, Assault could use a bit of a downgrade.

The Shield ability was really useful, but kind of annoying. Having to remember to activate it all the time was annoying, especially since the cooldown means you can keep it up almost all the time anyways. I'd suggest shifting it to either a passive ability (recover a point of shield every turn automatically) or make it more potent but with a shorter duration and longer cooldown.


Commando
I wasn't so keen on the Commando. It didn't seem to fill any particular niche and wasn't good enough as a general purpose gunner to make up for it. The sawn-off shotgun was decently useful early on, but rapidly fell into disuse as the enemies got tougher and it was no longer capable of finishing anyone off. Even if it were unlimited I'm not sure I would have bothered with it very much. As it is, I feel the Commando is the most sideline-able class.

It's possible I only feel this way because I rolled Hip Fire on so many other soldiers, though. That ability was far and away the best bread and butter style ability in the mod. It was pretty much always useful on anyone and basically just better than Rapid Fire or Chain Shot.


Demolitions
Demolitions largely suffers the same weaknesses of the vanilla Grenadier: as the missions get longer, its limited explosive charges become more and more inadequate. By the mid to late game, they just don't have enough stamina for the longer missions. Breaching Round and Flash Round seem kinda interesting for the early game, but they pale in comparison to grenades and the arc thrower and by mid to late game are almost never the best use of an action. Remote Start ended up being more useful than expected, but I'm not fond of relying on lucky map generation to get use out of an ability. Explosive Shot is really useful, but it felt like I only really brought a Demolitions along for an extra use of Frost Bomb.

I feel like the class could really use some kind of reusable AoE explosion to keep up with the rest of the squad lategame.


Gunner
Not especially remarkable, but a very solid class with Bulletstorm, Squadsight, and some decent ammunition. I rolled Overdrive on my gunner which seemed like one of the best synergies for that particular ability. Gatling Fire was a very useful lategame ability and was key to beating high HP foes. However, aesthetically it could use some work. Right now it looks like the gunner just takes one shot and it's pretty hard to tell if it's working properly or not. It would be much better if it acted like Rapid Fire in appearance.

The combat knife felt pretty inconsequential. My Gunner was too slow to end up on the front lines where the extra attack might matter and once I got Bulletstorm I have a hard time imagining a situation where the knife would actually be the best use of an action.


Mage
Mage was, probably unsurprisingly, my runner up for MVP. It's mostly just a Psi Operative, after all. Restore felt pretty overpowered. It ended up being one of those "well, I better save it for when I really need it" abilities that I ended up not actually using very much. Either a ranged heal OR a two action point restore would be worth it on their own, both together is just a bit much. I feel like it would be a more interesting choice if Restore were removed and replaced with a healing ability and an upgrade to turn Inspire into a non turn ending ability were added to the tree. Teleport was pretty neat, but it feels like it really needs some kind of limitation. As it is, it pretty much completely trivializes movement and positioning for the Mage. It also really should have some kind of visual effect, it's kind of jarring without one.


Sentinel
This was an odd one. Scouting and sniping didn't really synergize very well so I had a hard time making use of these guys. I went with the pistol side of things because that seemed better suited to close range, but the damage was just too low to keep up with the rest of the squad. Further, I'm not sure if it was more because of the innate stat growth of the class or Not Created Equal, but my guy wasn't really accurate enough to snipe until pretty late in the game. Also, I'm not sure if it was intentional or not, but Pot Shot dealt damage twice instead of double damage. I'm not sure if that would be a buff with certain ammo types, but it definitely made the ability less useful against armored targets than I had hoped.

I feel like the big problem with this class was that it had a lot of ways to get into and maintain concealment, but there wasn't really much of an advantage to actually staying in concealment.


Support
I tend to play pretty conservatively, so I pretty much always brought a support along with me. Healing Darts was a solid alternative to the Specialist's gremlin. I liked not having to always use a utility slot on a medkit. It would really benefit from a better visual effect, though. Would it be possible to change the particle effects so it at least looks a bit more different from a regular attack?

The big problem with this class, I felt, was that the arc thrower line was so much better than the holotarget line. The arc thrower plus warning shot meant one of my Support characters was pretty reliably taking out at least one enemy a round and Chain Lightning was pretty close to a "free turn" ability. Holotargeting was useful, but just not in the same league. It also didn't help that several of my soldiers rolled a Mark Target ability (not sure where it came from) that was almost as good as holotargeting for much less of an investment.

Another problem with the class is that unlimited healing is a bit on the tedious side. I had a few missions without timers where the sensible thing to do was to just completely heal everyone before moving on, which seemed wrong. I feel like it would be better if the free heals were turned into healing dart upgrades instead.

Technician
Technicians feel like the kinda got the short end of the Specialist split stick. Supports get the reusable arc thrower and holotargeter, but Technicians are stuck with per mission charges. I took one with me as much as possible for the sake of Haywire Protocol and skullmining, but my Technicians ended up spending the majority of their time as the designated shredder. Shock Protocol was an occasional lifesaver, but for the most part the gremlin abilities never felt good enough to justify their limited charges.

Thinking about it, I actually wasn't so keen on the Specialist split. I feel like healing and hacking are pretty essential for every mission. In vanilla, having a Specialist on every mission to fill both those roles was simple enough, but having both a Support and a Technician on every mission meant a lot less room to include less essential classes. I don't think I ever even deployed a Skirmisher this game. I feel like it might be a good idea to give healing and hacking to other classes as well (maybe Sentinel and Commando?) to encourage more mixed squad compositions.


Anyways, those are my thoughts. On the whole, good work. I enjoyed using these classes on my playthrough. Assault was my MVP class and Hip Fire was my MVP ability. I hope some of this feedback is helpful!