Who said something about rushing the next console ? I dont expect the 4DS to hit anytime before Fall 2015/Q1 2016, maybe even later - and the home console to follow a year later. So we are talking about 3 year for now - thats everything but "rushing" especially.
And the big difference is that not all PS3 type games run on Vita - why do you think Boarderlands looks like that on Vita ? Or we wont see GTA/RDR Open world games on Vita with the same graphical fidelity of PS360 titles ? Sony does all they can from a development tools standpoint - still there is a big difference in hardware power and architecture. With 4DS and Nintendos next home console you shouldnt have to worry about stuff.
Its better to have a base system and then up port to a higher powered system, than developing with stronger specs only to somehow dumb down the game for other platforms.
4DS - Base specs for the unified platforms and able to play the titles in 480p/qHD
Nintendo homeconsole/hub - Overclocked version of the SoC, runs every 4DS game at 1080, runs exclusive games as well, cheap
And whats wrong with a cheap console ? We have mobile SoC being able to run Unreal Engine 4 with most of it features.
https://www.youtube.com/watch?v=LMcscM_Hogc