That's good too :) but still — there is literally no reason for me as a player, to not pick specializations for EVERY of my skills, the moment they reach the required level. I think that some flat cost in Story Points would lead to a situation, where at some specific level it's more cost effective to get a specialization instead of next skill level. Then you, as the player, have to decide if you want to buy a nice bonus just for your specialization. If it's free, literally everyone will be a specialist in at least several skills, eventually. It's a pain in the ass to track and remember.