I don't think Goins really factors in to the equation. He looks like a perfect bench IF, which is more than I ever thought he'd become. Good organizations don't put players in roles that demand absolutely every last ounce of their talent. Penciling Goins into an everyday role means he's going to be hard pressed to be close to average at it. I think you put him on the bench, and then think about planning on him as a starter when he absolutely kicks the door down.
I think the only question that will matter re: Tulo is "Is he going to be worth his contract over the next five years?". If he comes out of the gate with a league average bat through 2-3 months next year, the answer to that question is "probably not" and you think about moving him while you can. If he comes in and looks like vintage Tulo you keep him and enjoy the MVP production.
I doubt Goins moves the needle on that kind of decision at all. He'd have to look like a league-average hitter for that to be the case IMO.