Yes for everything except human shield (as i'm not big fan of killing). Hostages mode (you have some people in, let's say, bank, so police won't attack immidetly and you have time to escape) - yes. But all of this (or most) are in plan probably, they just focusing on other things right now.

Human shields can be used in a non-lethal method. I guess it would line up with the hostage mode. Basically having a human shield would make cops not shoot at you, letting you maneuver back to your getaway car. Hostage mode sounds like it's keep cops at bay while you're still robbing. Taking a human shield could keep them at bay while you're trying to escape.

Or, to be quickier, using some melee weapons, like club/baseball bat/leather saps

i'd fully support some kind of hostage mode with all its implications i.e. human shield etc i thinks its a really great idea

Hostage taking is something that has been discussed on a general level, but not yet decided on. While it would be a cool and a fitting feature, it's also a big concept design-wise. Being able to take hostages would likely affect everything from UI to AI level to campaign to skills design, which in turn means a lot of design and implementation work. So this is still out there.

However, the original idea with punching people out always was that they would eventually eventually wake up. This should make heists more dynamic, as you cannot knock out everyone you meet and slowly advance through the whole level. Waking up problems can then only be countered by either killing the NPCs, using goons to guard them, or by using limited use items such as zip ties and duct tape to tie them up. We're quite confident these items and mechanics will be included in the future updates, and that they'll improve the gameplay.

Finally, melee weapons. Similarly to hostage situation, this is something that comes up every now and then, but has not really been figured out yet. Melee weapons will likely be much easier to implement though, and as they too are cool, they're quite likely to be in. How and when is a different matter.

This is where we are at the moment; please keep posting your ideas and feedback, they help us shape the game and give us perspective. Speaking of, what are your thoughts of the KO/waking up concept described above?

That reminds of the takedowns in Invisible Inc. Basically in that game, when you take down a guard, they stay unconscious for a few turns before waking up. You need to keep an agent with a downed guard to prevent them waking up

I think having to worry about knocked-out NPCs waking up would add an interesting dynamic. I tend to lock knocked out store owners, cops, etc. in rooms to keep them out of sight, but this mechanic would force the player to do that if their heist will take an extended amount of time.

To eliminate the problem of guards waking up I just lock them in a room after taking their keys :)