Depends on the franchises picked up...and how Nintendo revived them. New IPs are quite difficult to create, and there is no guarantee that the new IP will pick up an audience. However, there is already an audience and fan base for some of these neglected IPs. Of course I am not talking about picking up every IP...just choice IPs. And bringing them up to the forefront again with a game like Smash Brothers is a great idea.
I would love to see what Nintendo could do with Adventure Island, Bonk, Bomberman, Stryder, Mega Man, ect...and I know Nintendo has limited resources, but they could also outsource the games being created, with Producer Supervision from their directors.
It is just a thought...and perhaps not the best one, but if people are all talking about Nintendo buying Sega for the IPs...because Nintendo could make a better Sonic, who is to say Nintendo can't make a better, Shinobi...