I think to remember that Bioware also always encouraged people to play twinks, to play different class stories, different factions. As subscriber doing everything you would end up hopefully outleveled most of the time... so skip one planet except the class quest and do another one. I love hoth for example.... I'll do all planetary quests because I really like the planet but skip taris etc. without having problems reaching lvl 50 during my class quest on corellia. My mercenary plinged lvl 50 after finishing the class quest on Corellia (only class quest) and turning in pvp quest.