They're worth doing, but to buy them? No.
I wouldn't really agree, doing them actually takes me more time than farming enough EC for 10 points.Other than that I'd rather recommend them for people who want to bring the max out of their characters as already endgame, so I'd wait till I gear up before getting them.
Only reason I haven't bought them is because it states that it erases all titles but the questline ones and War Avatar titles. So the Holiday ones we got like i.e halloween 2014 will be erased. And I don't want to lose my titles, some you cant trade. (like the past halloween 2015 ones. Only account stashable I think). Plus I don't really feel like purchasing titles AGAIN when I got them free the first time. So, for me doing the quest lines would be kinda the only way to go. Which idm, just haven't gotten around to it.
Just farm them and save your money... or are you too bad for PvE?