Visage tips in general would be nice
Visage can work in a lot of situations. He gets a lot of kills in 3v3, but he is perfectly fine in a standard trilane and is good for occasional roams (provided you have enough damage to charge him up).
His main weakness is cross-map movement. If you do not have re-summon, your Familiars are left in one lane while you rotate. That isn't always a bad thing because you can use them to apply pressure elsewhere (especially with a Drow Ranger on your team) while you rotate and spam Soul Assumption in fights.