It took me about 3 to 4 days to hit max level back at launch. Probly would have done it quicker except the servers were constantly crashing. I think one thing people don't remember from when it was "slower" in STO, there were HUGE gaps between missions. You'd have to go grind out several levels on fleet actions, pvp or patrols to get to the next story mission every few missions. Now that there's finally enough missions to see a person from start to max, I think that's fine.
What I think they should focus on now (aside from bug fixes) is alternate methods of leveling. Different paths than the single linear play every mission in order.