Bladesinger is considered a poor PrC. You're losing out on arcane spell advancement, and getting a poor replacement list without any high level spells.

Basically, you're a gish, but you really don't get many of the benefits.

I like the flavor as well, in many ways, but it's probably self-defeating to go with the actual PrC. You'd probably be better served with a different build and your own fluff.