Garbage Stayman Responder bids 2 with shortness in clubs and a weak hand. Crawling Stayman Responder bids 2 with both majors and a weak hand. It is possible to incorporate all four types of Stayman into your system because they are complementary. I do and it works beautifully. 2 by responder promises at least five spades.
Any point count is possible.
3NT is a terrible contract that is well worth avoiding. After the disappointing 2 rebid by opener, responder jumps in his five-card suit to force to game. An invitational approach would have resulted in the partnership languishing in a part score. Without transfers, he could never have ended up in 3 . Opening 1 a and finding a rebid after a 1 response would not have been fun.