So, i recently gave this game a new try, after long absence. Fresh character on a fresh server. Now, my ultimate goal is to combine EVERY class in this character, if this is remotely possible.

My question is: When i begin, what makes most sense? Stick with one class for as long as possible, maybe even get to 60 and then start leveling all the other classes for the xp bonus? Or try to get to an advanced classs to make the leveling itself easier? What should i do?
Fyi: I do currently play an Arcanist. Is it even possible to go through the game in a basic class?