Sadly, I play with Project Balance and SWMH, so there is no Cumania and it's impossible to get a marriage alliance with Sarkel (the dominant Kipchak polity of the lower steppe) for "Political Concerns". The Alliance with Georgia doesn't usually last more than a year or two, either, as both starting Kings are too old, and Georgia is stronger in PB+SWMH than in Vanilla. And then there was just bad luck in my current game, my heir had all sons and so did Georgia's heir, so no new marriage alliance was possible. All that said, I was prepared to contest Kasogs and had the money for sufficient mercenaries to dwarf the Georgian forces, but shortly after the war started Georgia entered an alliance with the ERE and called them in and that was that. One close battle which I nevertheless lost and I was forced to surrender with -267% war score: insta-surrender, no choice. Then Sarkel immediately declared a Raid and when all was said and done, I was still standing, but it took a decade to claw my way out of debt.
It was fun, but strictly speaking, I would have been better off abandoning Kasogs and focusing all those men and money toward the steppe and not losing them to Byzantine swords. Georgia didn't get to benefit from it, either, as inheritances have resulted in Abkhazia going to the Byzantines within one generation.