Vita should have been delayed a year or at least launch summer 2012
God no. They needed to do the exact opposite. Sony needed to have Vita released in unison with the 3DS - summer of 2011 at the absolute latest. There's simply no excuse for giving 3DS a year head-start - a year to work through all of their pricing and software issues, and a year to build up a 15-million unit lead and secure a bunch of 3rd-party support uncontested because their competitor wasn't even on the market yet.
You just don't give the successor to the most successful handheld of all time a head-start. Not if you have any intentions of actually competing with them. It really is analogous to MS and Nintendo giving the PS2 a year head-start, following the massive success of PS1. Sure, the PS2 was underpowered in comparison, but it could still handle all of the same types of content. Much like the 3DS is underpowered in comparison, but can still handle all the same types of content.
The PS2/XBox/Cube battle was over before it even began, and the Vita/3DS battle was also over before it began. I can't say it enough, but there was simply no excuse for launching late with Vita. If that means they had to have a backup plan in place to go with different hardware if Vita wasn't feasible in early 2011 - then they had to have a backup plan in place. Just sitting on the sidelines for a year was an atrocious decision if their product wasn't going to be wildly different from the 3DS.