One of the subtler, yet most notable ways in which fiction and Roleplaying Games differ substantially is in the growth and development of main characters. See it is RPG tradition to have characters 'go up a level' or otherwise earn their Experience offscreen in-between all the fun stuff happening, which is mostly because that's just how D&D always did it. Whereas in fiction characters often power up or learn new techniques in the middle of it all, or even stranger, don't actually ever change.
There is also the fact that in fiction a character is often good at a couple things and maybe picks up a couple new ones down the line, while the by-and large trend in RPGs is to have dozens upon dozens of little abilities that give a +1 here and a +10% there every single session and before you know it you've picked up a second character sheet just to keep track of it all.
Now I'm not going to say this is wrong (though it is, at least for me, annoying) but it certainly doesn't represent any kind of fiction I can immediately think of. And yet I will justify it, up to a degree, because giving Players new toys often is an excellent idea. When you're in the middle of a dungeon romp, defending your home from relentless aliens, investigating a series of murders, or in the middle of any other kind of story arc, it feels great to actually look at your character and get a feel that you're getting somewhere awesome even if the current storyline is not anywhere near completion.
And that's the short story behind the division of Upgrades and Enhancements. You can pick up Upgrades right as you need them in the middle of a battle, and they're all pretty darn significant (and expensive) so as to avoid a glut of easily-forgotten abilities. Enhancements meanwhile let you power up your base stats or make your Upgrades stronger, either way you never feel like anything you really want to get is off-limits until it is the arbitrary time to level up..
So I like it. It is dynamic without being all over the place. Then again I am biased. But like oh so many things with this game I'm going to fine tune it a little. First of all, Enhancements to Upgrades sound cool until you realize, after spending those Genre Points to save the day, that the Upgrade in question isn't very good without pumping more UP into it. Then there's Common Enhancements, which increase your performance at an absurd degree by increasing base stats for a very low cost.
Which is funny because the former was meant to be flashy and awesome and the latter is there to give people a way to spend the UP they don't know what to do with. For this reason Upgrades are going to be bought at full power right from the start, no more Enhancements to individual Upgrades. Common Enhancements are still going to be there, but because they are so powerful and make it so easy to specialize, they will have incremental costs.
So basically, Enhancements are becoming an UP-sink when you're done getting cool Upgrades and Weapons. You can get them from the very start if you really want them now, though. The changes should replicate the dynamics of anime action that much better.