My own thoughts:
I actually really like the way the turn based combat works in Fallout, the only big things I would change would be to have a way of changing the viewing angles and a way of attacking while moving. In Fallouts 1&2 I love to stand just outside a door and then use one action point to step out, fire a few shots and use my last action point to step back. With an updated combat system it would be possible to start 2 steps away from the door, take one step and turn slightly to face the door (assume the door is to the top of the screen you’d stand at an angle like this / )and start firing an SMG, the next step puts the player right in front of the door, turn to keep facing it ( | ) and the next just on the other side of the door, again facing the door ( \ ) at which point you could stop firing and take one more step to be completely clear of the door. Naturally spraying a room with bullets this way would have very low accuracy, but smart AI would rethink trying to run out that door to get to you.
Also there could be more emphasis on what movements the target is making, if any. Are they mid-stride in a flat out run making targeting more difficult?(Unless of course they are running straight at you, in which case your target is getting bigger) Or are they completely flat footed? What position are you in? It could be very effective to run a few steps, drop to a prone position, Fire, get back up, run and repeat. Then there could be something like Exertion Points which won’t replenish after each round like Action Points do but will instead be used up throughout the battle, maybe unused action points could be converted to exertion points each round.
Another mechanic that would certainly be possible would be for the player to queue up their actions, maybe there could be like a ghost image showing what it would look like to confirm that it’s really what you want to do, and then hit the Go button. Rather than moving and waiting for all the NPCs to move all the actions could happen all at once then pause again to allow the player to see what happened and to queue up their next set of moves. I think this would make combat seem a bit more fast paced and urgent but still retain its turn based strategy elements.
So is this something that could still appeal to any modern gamers, or am I just a gaming dinosaur who should go find a tar pit?