Endgame is not really my concern at the moment, as I'm quite a ways away from doing that. The original purpose of my question was to see if you can be a hybrid while leveling. I can always respec later, I know for endgame you need to focus on one tree.

But for now, I am curious about this because I only had points for the Infiltration tree yet I've been able to tank for my groups pretty effectively. Maybe part of this is because I spent so long leveling my Guardian tank, but I thought it would be nice to be able to fill whatever role a group needs me to fill (versatitlity).