I think the most obvious choices for future acquisitions are Bluepoint, Housemarque and Arrowhead. But at the same time Sony could keep funding their projects as 2nd party developers and only acquire them if they make any sort of hit that could become a tentpole for Sony (like they did with Insomniac after the success of Spiderman).
For acquisition based on relationships, i suppose RaD, KojiPro or genDesign, but the 2nd and the 3rd ones seems to value their independence pretty high so i doubt it.
Remedy is still too farfetched imho.
Other than thar, i would love for Sony to invest in a couple of AAA Japanese projects or acquire developers like Matrix Software or MediaVision, and try to give the 'Sony' spin to JRPGs.
Still, i think most of this will happen during the gen.