(Also posted this on the Discord for Vorochi's mods. Thanks, these have been a ton of fun to play!)
I would rank the faction ease of play something like this

**Easy:**

*Traitor Enforcer:* The easiest faction to play, you get spectacular freespawn in terms of quantity, quality, and how much work it is to get it deployed. A variety of other interesting tools, and I felt it was a really rewarding onramp to this mod collection.

*Archmagos of Mars:* If you luck into a tech priest, you can spend income to earn more income over time, and at the same time you are investing in great garrisons to protect your terraforming. Even without, you have a good roster of affordable military options. Even after the nerf that keeps you from hiding behind 50+ disposable civilians on campaign, possibly the most terrifyingly efficient turtle+economy faction I've seen in this game. And also pretty fun to play, my second favorite.

*Cadian Castellan:* Best quality freespawn, with excellent supports from a variety of angles. Though there's a few things worded in ways that might confuse players (it is not super clear that your artillery needs a special artillery commander to work, for instance), and you get way LESS soldiers than renegade guard, the faction does not need much micromanaging to do a very effective job.

**Moderate:**

*Lord of Contagion:* Your freespawn is OK in early game, you have a clear goal to save Hands for and a secondary currency to spend more freely and you do get a resilient flying thug to scout around, but the slow units are often frustrating. Faction gives you room to make mistakes before you hit a threshold that enables the crazy-good stuff. Risky summons can put you in a bad situation, but I found that my Beasts of Nurgle and Monster Toads were pretty good at tearing apart hostile duplicates with a little gun support without me taking significant casualties.

*Aspiring Sorcerer:* One of your core iconic units being Slow is a real drag, and the choice paralysis of 9* (not counting swordy recruitment guy) sorc orders that might not actually do what the flavor text suggests means that players might be doing a ton of save+reloading or having to break out the text file to begin to understand what they are doing. But hey, the preacher recruitment is still a good backbone for your faction, even if your guns are worse and sometimes you don't have them. Unlike 3/4s of the factions above, I feel like this faction really encourages you to invest in basic troop upgrades.

**Hard:**

*Twins of Ulthwe:* Your units are expensive/difficult to replace, the faction punishes sloppy play and encourages you to spend valuable resources on methodical scrying and thinking multiple steps ahead. You also can easily end up with the Twins having whole battlefield spells that can hit their own troops and potentially cause issues. Level 3 magic is a double edged sword.

*Hive Tyrant:* Getting the hive fleet's attention is what you need to do to get affordable commanders to do all the rituals you need and shepherd your forces where they are needed. Starting players might easily delay that by grabbing Lictors and using them as basic army herders or citadel defenders, increasingly terrified at the prospect that only the leader can do vital rituals. Semi-stupid units will run off and get killed if you micromanage poorly or don't study your units carefully. It is easy for a starting player to think they put a garrison down, only to get sniped by deer. Another trap for beginning Nid players: the lure of keeping villages to collect gold taxes to build those lifeforce pylons. It's a lot of gold, after all.