depends on golds (there are some decent ones like bernice , but they aren't generally that usefull compared to plats) , but if you're willing to reset accounts , u should aim for plat/blacks. I mean , at least theoretically , you should get a plat on your first summon in about 10 out of 100 new accounts....and a black in 3 out of 100. Some people just make 1-2 summons because it's not worth raising scs for more summons on a new account.

Generally most black are usefull , but stuff like aisha , nanali , despara and so on are pretty damn good to have. Even plats like elziabeth , gelius , jerome , and so on