Brett B is most likely the one you're familiar the most, horse blanket, earthy and so on.
Then you have Brett L, which really is a strain of Brett B, a bit more fruity.
Brett C is another option, I used it for a Tripel and so far so good, hay like notes and some fruit notes, but it's more expressive in the nose than on the palate.
Brett B is probably the best option as that's what's in most commercial brett'ed beers you may have tried before, but, take into account that you're sitting at 1.024, bottling a non stabilised beer over 1.008 is considered dangerous among lambic brewers so to reach a safe FG you're looking at a year or more ageing time, unless you go the stabilising route
aside: i don't believe that we can generalize quite so much anymore, at least not for brett B. Brettanomyces bruxellensis is a species, same as Saccharomyces cerevisiae. so just like you can't attribute a single set of characteristics to sacch (RE: chico vs. any belgian), you can't describe brett brux as a homogeneous whole. check out the flavor descriptors for single-strain brett offerings at the Yeast Bay:
- "lemon/pineapple, with a restrained funkiness"
- "tart tropical fruit ester profile reminiscent of SweeTarts"
- "mild tartness and soft funk with a solid backbone of tropical fruit esters (papaya, guava, pineapple, guinep)"
- "complex tropical fruit that is dominated by pineapple with a noticeable earthiness"
- "delicate mixed fruit cocktail character that touches the palate just enough to let you know it's there but doesn't overtake the character of the beer, and exhibits a very restrained but pleasant earthiness."
- "complex and multi-dimensional Brettanomyces character (...) a mixed dark berry quality with earthy undertones.
those are all from different strains of brett B. as was rightly pointed out, for some time Brett L ("Brettanomyces lambicus") was assumed to be a different species than brett B given how different it tasted, but genetic testing has confirmed it's brux.
the barnyard/horse blanket/earthy/etc. characteristics traditionally associated with brett brux is likely due to the prevalence of the Orval strain of brett b, which for the longest time was the only widely-available strain of brett available to homebrewers. the brett B from White Labs and Wyeast are Orval.