That's what I do.
Being one of those fans who likes to have things consistant wherever possible, I often twist things a bit to suit my personal desires (I just get maximum enjoyment out of shared universes, the bigger and more intricate the better!) So this sort of justification is fun for me. If Emperor Mow'Ga during the "Second Empire" could lose entire conquest fleets in Breen space (which the Star Charts book placed at some distance from the Klingons), then other expeditions could have jutted out under or over the still-expanding Romulans and troubled weaker worlds in proximity to Thallonian space? Explaining Resaurus and the Brikar. Klingons seemed to be presented as more decentralized in the 22nd century, so entire Houses could have been striking off to conquer or raid distant worlds even if the High Council wasn't interested.
So I prefer to have the Brikar contained and the Klingons being the ones likely to stretch their hand across the stars. And the Brikar, I feel, need to be near Thallonian territory because they chased back the Dogs of War, and the Dogs are localized to the Thallonian border regions, with a few raids on other nearby territories. So I picture the Brikar as a contained cluster of worlds above or below some part of Romulan/Federation territory, between the Klingons and Thallonian space.
Although, I was using TOS canon as my guide. 
BTW, there are a few others like a Mugato that joins the crew as noted, but most Star Trek crews we've seen are predominantly humanoid. I can't remember whether it was a TV episode of TNG ("All Good Things"?) or in a novel, but I recall that being by design and involving Q somehow. Yes there a few non-humanoids out there, but that's a small exception to the rule.
