Tom was exactly what Vito wanted him to be - a hyper-rational, conciliatory, smooth attorney.

Vito wanted Tom to counter-balance Sonny's temper with coolness. He also wanted someone with an impeccable demeanor to be the legitimate face of the Family. Remember his quote from the book about one lawyer with a briefcase stealing more than 100 men with guns.

I don't think Vito's view of consiglieres was much different than Michaels. For all the reverence Genco receives, I question how important he really was. I don't remember anything from the book or movies that indicates Vito really consulted with Genco on strategy. I don't think Vito felt he really needed a real consigliere - a stance which backfired when Vito was taken out of commission.