What's slightly interesting is how much of the player choice is front-loaded - in the character build, mostly - and how much is in the process of battle.
There are lots of systems (most versions of D&D 3E, including Pathfinder, for instance) where a lot of the player choice is front-loaded. You have an idea for a character build and you choose abilities and equipment to suit. You hope your build is reasonably flexible but there are always limits - there's very little that a slow melee tank can do about flying monsters, for instance - and it's a lot of fun optimising your build. But if you didn't make the right choices (because you didn't have "system mastery" or whatever) then it's not a lot of fun, and once battle begins, most builds don't have a lot of player choice, because you chose a specific build and you're hoping it works, you can only really press the buttons related to your build.
There are lots of systems where most characters have access to most options, and so the player choice is mostly in how you use those options in the actual fight. This is common in games that model wuxia or similar, because most wuxia/xianxia protagonists do fairly similar things - leap around, hit with swords, nerve blocks, use qi to increase damage or protection, and so on - and so the fun is in working out how the specific system works for modelling those and what you feel best (and coolest) doing. Again, "system mastery" is an issue - make the wrong choices and you're going to get impaled, or at least feel less cool than you expected. Your build is less relevant, though of course having high stats matters, and emphasising strength, mobility, or qi pool is all going to matter. If you spent points on an exotic technique that's cool too, though it depends whether it was worth it and whether people get bored of you breaking out Poison Toad Breath every time you get in trouble.
(We're playtesting a system similar to the above at the moment, developed by one of my friends.)