There is quite a dearth of well designed RPGs out there. At least ones that get played in my area. That said the diablo 3 free play weekend (yeah stress test whatever, it was a demo weekend and you know it) brought something up that I thought worth considering. While Diablo 3 may suffer in the replayability column due to the way the skills are laid out, tabletop RPGs could learn something from it. To sum up the skills in brief, as you level up more skills (which would more likely be described as powers or spells in a tabletop game) are unlocked for use. You have skills you can use over and over without limit and the rest are on based on various resources (mana, ki, rage) that either replenish over time or when you perform specific actions (usually attacking with your over and over skill). The special part is that you can only use one skill from a group at a time. You can switch to any skill from that group with a few seconds of switch over time, enough that you don't want to switch mid battle, but not long enough that you can't switch between them. This may hurt the replayability of diablo 3, but I believe something like this could work wonders for a tabletop RPG. Especially if tempered correctly. Swapping out your skill in mechanics for your skill in bluff might be out of the question, but what about swapping out your improved trip feat for an improved disarm feat. Or your "do lots of damage with poor accuracy attack" for your "precise attack that doesn't do as much damage". The big issue in the fighter wizard gap in 3.5 revolves around flexibility. Wizard has a tool for any situation, assuming he prepared it. What if the fighter could switch stuff around so he could have a larger stable of useful abilities. Food for thought. Admittedly, Tome of Battle goes down this route somewhat with its maneuvers readied vs maneuvers known but I'd make it possible to grab any maneuver from the entirety of your class maneuver list rather than the subset that is your maneuvers know.