I see no reason not to add a pause feature; if for no other reason than to stop the repeating banter around NPC's. The snap to target works as well but has many issues of its own such as bunched up or overlapping targets, and moving targets as the author pointed out in his original post. Further, this is not photoshop and for anyone not used to that type of thing, it will be as unintuitive as right clicking is now. Even knowing about right click and select attack, I still find myself left clicking most of the time and every now and then, messing up.

Another solution would be "execute" popup after a command is given or simply a delay so that one can undo a mistake. But this can get really annoying, then again, this is a turn based game after all.

2 - Yes. Speed up actions would be a huge boon.

3 - This could be easily implemented by making only the controlled PC vulnerable to environment when out of combat for say 15 seconds or so.