i've pt's w/ some /thf in pts before for fun, really isn't bad. mnks are not really a soloable class, they have potential for incredible fast bursts of damage, and are freakin awesome btw in cop bcnms. But they are not soloable like Nin or Thf or Rdm, bc they don't have long-run durability which is really what soloing is all about.
subs
mnk/whm for chiblasting HNM's like Kirin

mnk/nin for some mission bcnms, and ksnm(thinking ODS) and also for mid-level soloing

mnk/war standard xp pt sub, actually the standard sub for most instances.

mnk/thf just for having fun, mnks don't sataws as well as jobs like sam or drk, but it's still viable enough to not turn ppl off, and it's something that can be done when someone's bored to tears of mnk/war

oh and someone mentioned this in another thread: i don't understand why you would delete/remake characters like you do. People that do that, in my experience, are ppl who like making characters but have no inspiration to do anything with the game or don't have the determination or skill to go further, and are generally wasting their time, though if that's what you want to do, go for it. just seems like such a waste to me. changing from one job to another is fine, but makes so much more sense to lvl the other job on the same character. If you just like building characters there are better games than ffxi for that. ffxi is only a mediocre game for the first 65 or so levels. after that it's the best, but before it's just monotonous lvling up in boring areas and doing stupid uninspired missions. to each his own though i guess