1) the "alternative", is not really an alternative, is how Halo have always been in matchmaking, JiP is a cheap and mediocre solution to solve quit problems.
2) Not Having JiP means Im not going to be trown into undesirable situations, heck, I dont want to start a Matchmaking game halfway trough no matter if the team Im joining is wining or not, I want to start the game from "0".
1) A mediocre solution is better than no solution at all. Perfect is the enemy of good!
2) You are thrown into an undesirable situation the minute someone quits your team. And, I'd argue, the minute someone quits the opponent's team, too.
I think the best solution for now is to simply have casual playlists with JIP.