It is true that you rarely need to restart vita but at the same time cold boot gives you a lot of options like downgrade/upgrade, write protection to parts of firmware that you don't want to upgrade and stuff like that.
With proper hack you can essentially run newer firmware with parts of old one. Meaning latest updates, full access to PSN etc. At least this is how it is done in 3DS scene.
I guess that's something I would look forward to









