Go with wrestling or (Gulp) Catch. Learn to use the guard though.
I say this because your stand-up grappling with MT is mediocre at best. Wrestling experience will improve your clinch skills drastically. It will provide the takedown and control positions. Catch will teach you the subs. Neither make extensive use of the guard. So you should at least learn the basics of that, and also, how to get up safely.
Just my opinion.
And this from a BJJer... SOB! But I wrestled first...
Anyway, what I'm trying to get at is that I haven't seen a "complete," grappling style yet. BJJ schools tend to be weak on takedowns, Sambo guys sometimes don't defend chokes too well, and aren't sure how to get by somebody's legs, Judoka are often weak on the ground, wrestlers frequently don't know subs, and Catch wrestlers seem a bit stymied by use/opposing the guard as well.
This is all in keeping with each arts philosophy mind you, and I'm not knocking them. And you will find many who don't fit the description--I'm painting with REALLY broad brushstrokes here, and it varies from school to school and person to person.
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