I see what you're saying about T2 but I don't think Sony can get close to affording them. Also, I really don't think Microsoft, or anybody else, will buy Nintendo. Nintendo are so successful on their own, have bags of cash for rainy days, and are ofc Japanese so they probably don't wann be bought by a foreign company (just how it is).
Speaking about Japanese studios, that's where I think Sony ought to strengthen. With Jim Ryan going, I hope and think Sony will end their anti-Japanese stances they've taken recently. Buying one of the major Japanese devs like Square, Capcom, Sega/Atlus, Fromsoft, or even Konami for the IP, would be a move that would really diversify their 1st party line-up and the strength of their presence in their home market.
And yes, I do also think they should continue to acquire smaller, talented devs when the opportunities arise.
Finally, I would strengthen their China and India strategies. Maybe even open up a full fledged studio in Beijing or Shanghai if possible. Maybe Korea is an option to open a studio in too?