Bassanio's gravestone does not exist within Veronaville, so he can't be made playable without the use of hacks. As a result, the only indication of Bassanio's existence is provided by the family tree of his descendants. According to his SimDNA in SimPE, his hair was red before it turned grey.
Bassanio has no memories of his wife, and although he has the memory of doing WooHoo with Mystery Sim, he doesn't have the memory of Valentine's birth. So basically apart from the WooHoo memory, he only has Create a Sim memories. Bassanio has no skill points or personality points, and if he is resurrected with hacks, he will have a random set of interests. Not much is known about him except the fact that he is the Monty Founder.
Resurrection tip
This Sim has no character data and cannot be resurrected in-game. For more information, read this guide.