Mass Effect 3.5B: Taste the Rainbow (Story and Ending Discussion; Spoilers!)

[Arbitrarity]

That's incredibly optimistic; even Wrex on his own has very problematic leanings. ("You haven't seen how fast we can pop 'em out.") So you've basically got one Krogan - Eve - standing between the rest of the galaxy and an expansionist krogan. At best (under Wrex) they just want more room for their population to explode. At worst (under Wreav), they also want revenge. And they might want the latter anyway if there are too many Krogan for Wrex/Eve to keep in check.

Their high birthrate wasn't a problem before uplift because Tuchanka was so hazardous; they conquered the planet almost through attrition. On less hostile worlds, there'll be nothing to counter their baser instincts.

Given the lack of relays, this might turn out to be tolerable for quite some time. Since the relays are gone, Krogan expansion speed is limited by whatever FTL they have developed, and they will also use space more effectively; FTL limitations mean they'll colonize more than just systems with relays in them or nearby. I suspect that this will take them some time (on the order of many centuries/few millenia) before they'll necessarily come into conflict with anyone. That should be enough time for them to develop culturally, as they need to.
If you talked to Eve, you'll know that Krogan culture has stagnated since the genophage, because the females have been marginalized to a significant degree. In fact, she's the only female krogan we EVER talk to ingame. While that doesn't mean she's representative, her descriptions of female krogan imply they're much different from the males we see.
Also, Wrex is likely to have a rather large part in new children. It's been noted several times that he's a mutant, so that could precipitate some degree of genetic and cultural shift.