Hmm..
Well, I assume you are not playing on stadium, cause if you were, you wouldn't lead with Jynx.. BTW, Gengar is a faster sleeper, but with Mewtwo's running amok, leading with it may not be a great idea..
Anyway..
Jynx: Without sleep clause, this will be incredibly effective with double-team.. No one will be able to evade up against you, and you wont be able to be stalled since you can sleep your opponents.. I recommend DT over psychic, you may want to keep seismic toss to help kill off starmies and other Jynxes and such..
Mewtwo: Meh.. Fine.
Weezing: Well, if you are going to Haze Mewtwo's will be able to switch in.. Also, all in all haze is a highly over rated move IMO.. Unfortunately it get's rid of rest, so you will not be able to switch in, haze, then switch out safely.. Also, your team looks very offense oriented rather than defensive, maybe you should try just killing before they get the oppourtunity to kill you, rather than trying to counter their strategies like that..
Tauros: Go with DT, Rest, Bodyslam, Earthquake.. without paralysis OHKO's will be almost completely useless.. Especially with Mewtwo's about..
Dragonite: Fine, I guess..
Sandslash: It'll be difficult to get this to work so well without Paralysis support.. Set is alright, although I prefer bodyslam to rockslide when you have no STAB.
Hmm.. Ok, I would want a second sleeper if you have no sleep clause, because that is just how useful sleep will be.. I think you may find yourself relying on Mewtwo and Jynx a great deal, they are all you have that can deal with special attacks, and Mewtwo's and Jynxes will ensure special atacks are common..
I dunno how useful I was, I have never made a team for this sort of battle before.. Anyway, good luck.
Have a nice day.