Captain Grimm reminds me more of Captain Lawrence from the Temeraire Series by Naomi Novik than Mal.
Yeah, Mal is somewhat less-than-impressed with the idea of always being calm, collected and utterly unflappable in front of the crew. Maybe Mal pre-Battle of Serenity, but I doubt it. Captain Laurence has the advantage of commanding a similarly greater number of crew members than Mal, however, plus his 'ship' is very much sentient. (I don't think I've ever heard a better description of Temeraire than 'insouciant but understands the need for cooperation'...)
I'm torn between Folly as an Odiana (albeit a non-sadistically malicious one) and a River Tam-type. They're both far more dangerous than they'd seem, and both a few rungs short of a ladder to the point of needing to be guided about.
Rowl is Kitai or Doroga. From his very first lines he sounded like a Marat. (Probably due to the Marat thinking more about the here-and-now than Alerans, just as the cats think more about the here-and-now than do the humans.)