Levels are strange things in MMOs. Essentially, they mean very little.
You could design a game, for example, where it is mind-bendingly hard to get to Level 20, but each level you gets TONS of cool stuff. Or you could design a game with the same content and 100 levels and you simply get less cool stuff per level; sometimes even nothing.
So what sort of level do you want to reach as the cap in TOR?
Do you want it to be a really low number, but extremely long and hard to reach each new level, rewarded with lots of cool stuff each time you crack a level?
Or do you want leveling to “feel” faster by going through more levels in the same length of time, even though you’re still doing the same work as the previous example?