i might be interested,though it looks like you want stuff that too hard for me,thouhgt I'd run a tour suggestion by you,. a mexi-sampler.With three weeks you could get; 4 days on Micos,Valles, Sta. Maria day run, +? based out of Micos;4 or 5 days Veracruz=Alsaseca,Antigua,FILO/BOBOS/TATEMPA,ACTOPAN,based out of Tlapocoyan,Jalcomulco,and/or Jalapa
3 or 4 days Oaxaca coast PACIFIC,Copalita,and Zimatan
2 days Agua Azul and Palenque ruins
6 or 7 days predominately driving and rest
It,s always a toss up between sampling as much as possible and staying put and maximizing one or two areas.This plan is ambitious but doable,but expect something to go wrong somewhere along the line.All of those areas offer both expert and intermediate waters.Have fun whatever you end up doing.