Would putting on the output buffer in the Crybaby itself help more, or should I try out other wahs?
it might.. but the crybaby may be limited... I have a crybaby that has experienced the same problem, found that boss pedals work ok with mine,, but I know what you mean, I've also found that when I use the cry baby with certain amps model's on my line6 spider III it can be crap or good, iv also found that you can get better results with distortion if you turn up the mids on your amp.. I could be wrong but doesn't the MM have a serious scooped mid section to its sound??? that could be the cause, seeming wah's adjusting the mid feq...
the foxrox retro fit has an adjustable gain control on it, so it might just be the oomph you need but it's hard to say without trying one. but I have heard really good things about it..
I made an output buffer for my wah but found I didn't really like it much, got the schematic from http://www.muzique.com/news/wah-pedal-buffer/
I also made one from http://fuzzcentral.ssguitar.com/mccoy.php
so if you want them shoot me your email & address on the Private message and il send em to you... I live in Australia so it could take a while to get to you, but I don't use them so they just sit here collecting dust...
as for my wah.. sadly iv given up on it.. it has a ton of mods that made it a bit better but I just don't think my crybaby was made for hi-gain. when I can track one down il try to get my hands on a Geoffrey Teese RMC Wizard wah... it's made to work with hi-gain & hi-output pickups so im intrigued...
anyways... hope this helped