as empire i had to skip all of nar shaddaa and only did a few quests in tattooine before deciding to go to alderaan, all the quests in tattooine were green when i got there and i was lvl 30 upon deciding to go to alderaan, which is 28+ i believe.
Since I had to skip two whole zones, and i dont pvp actively, or do space battles, and ive only run each flashpoints once, i think leveling is way too fast because ive already skipped two zones entirely.
It was because i did every little quest in Hutta and Dromund Kaas and was level 19 before i finished those, so once you get ahead at a low level it seems you stay ahead.