I think real-time with pause, with all the actions possible in a turn-based system available, is the best option. Although it can be fun, I've always found pure TB to be too artificial. The whole I shoot at enemy, then enemy shoots at me thing seems like I'm playing a glorified chess game, rather than something that's supposed to be simulating combat. Also, at times the TB aspect gets in the way when you're faced with an encounter that could easily completed quickly in RT, but in TB you're force to endure the actions of every little thing on the screen. There are some solutions to these problems of course, but I like the elegance of RT with pause, allowing me to dictate the pace of combat, rather than having it dictated to me by the game.