I don't see anything wrong with the Vita to warrant a redesign. It's a bit large but it's got a big screen and people complained when the PSP Go got a smaller screen. Its accessories are merely fluff, nothing really "game changing" like the Circle Pad Pro on the 3DS. Other than that the big thing would be internal memory (like the PSP Go) but they'd probably charge "premium" price for that and by the time this theoretically happened, memory cards (and possibly the Vita) would be cheaper.
I'm just waiting to accumulate funds for the thing. I think $250 is a reasonable price for everything, but I'll probably want $400 optimally for the system, memory card, and some games (I'll probably spend at least $40 on some PSP games that could really benefit from a second analog and the rest on some Vita games).
Nintendo did that and they didn't lose money. I doubt Sony would lose money from announcing a price drop. Gamers would flock to stores. They didn't drop the freaking steep price for some because they feel the price fits the device and its components.
Redesign and price drops both apply to Nintendo: they've dropped the price much lower than its initial price, then released that additional gamepad or whatever.
Technically they did, they're selling 3DS systems at a loss. And they only announced the price drop because of rather poor sales. While the Vita's rather stagnant in Japan I've heard it had some positive numbers in the west. If those numbers stay high then there's little reason to drop it.
The 3DS is selling well now but, again, it's selling at a loss. What matters is if they can push DS-level sales of software. Selling a million copies of SM3DL is nice, but they're not the 20+ million of NSMB yet. It could eventually get there but their banking on software.
Although Sony has learned that selling on a loss (and price drops for that matter) can do a lot for them. It practically saved the PS3. If the Vita really starts to flop like a fish out of water then they can pull some of that Sony magic again and turn a profit.