Hopefully this isn't another joke topic, due to the fact how easier roguelikes are easier to make... based on what people say.
# how could a roguelike benefit from tablet PCs concerning usability and playing?
PC vs Android... i dunno what android IS. So i have no idea.
# do you think that you`d like to play a 'roguelike' with that non-standard setting?
I like having a customizable world, or hell, have one specifically designed, like a world thats like ours.. probably.
# what content should be in (important for a first version)?
Well, an important thing should be this. Firstly, there needs to be the basic necessities like combat, chatting, movement, and so on, then later making chatting more efficient to allow peaceful negotiation to try talking down criminals. Then later, since it's realistic, a forensic part, allowing investigations to continue to send others across the world to find them.
Basically, what i would do it work on movement and combat, and the start of the policeman career as a mere recruit training to handle things, from handling in keeping up with running criminals (stamina), making sure you can shoot straight... even though guns are hard without knowing how the wind and gravity pushes the bullet, which a recruit wouldn't know... and probably a lieutenant? I'm not sure.
Anyways, i don't know how law enforcement fully branches, but i think it starts from a recruit, which is trained until they pass, then pushed in as a police officer, then they work hard alongside a partner for... whatever... until you get in on some action as you patrol the streets, or whatever. I don't know whats further. Maybe you just do a lot of work until you're a lieutenant, than eventually when the chief steps down you be him? Or branch off to be a forensic specialist? Maybe control the entire police force in the roguelike? I don't know.
But yeah. Basic combat, movement, and the start of the policeman career. FBI career could come in a later version, as if i'm not mistaken, SWAT is also part of police, so theres another way to work it.
# would you like to have complex tactical combat, how could it look like?
Could be anything. A policeman can't be too rough, but if required, they can hit that point. I guess if a proper fighting system was in order, which can branch off not only in natural fighting, but maybe where they can go on vacation every now and then to have some martial arts training, they could work alot easier with melee combat.
Shooting... probably the same thing, unless you do aiming and all that on limbs. Not every cop shoots to kill, but if it's the only way to stop them, like if during a situation that requires it, not if they're running the hell away, then they'd go for the legs/arms... but if they, for example, have a hostage, and are open, it could take either two perfect snipers to blast that gun away from pointing her, but he might be able to move it back to her and shoot before you can run, so in a situation like that... you may have to go for the head, or do that gun blast thing and then the arm... but i've yet to hear of a hostage situation with more than 1 sniper.
# any ideas for a conversation system?
I've seen conversation systems that try to calm people down... i barely ever win.
Conversation is very hard, especially if you don't know what you're doing. It's more like a "try to get in their head" situation without them talking. If you can figure out how to converse right with someone, they can crack easily.
# any ideas how to 'simulate' driving in a turn-based game?
Never seen one try it, so no.
# would you even play it if it has only ASCII graphics in the beginning, thus the usability might not be that great?
Having the graphics customizable is easier, but for now, it could be kept curses, and have a text file determine what they could look like. Maybe add a way where graphics positioning is possible so people can make them look in different areas, like up, down, left, right, etc, but that would require ASCII graphics, so for now, it can go both ways.
Thats all i got on those.