Heh, "alliance falls apart once all the major powers fell". Dunno whether that would have included my fall.
I don't know how far ahead you people were planning, but from what I saw/heard it seemed both Vel and Homer (as well as me) had grown quite tired of managing their empires. My guess was that if a huge R'lyeh/Ermor war was to start, the winners would've noticed they have piddling 40% of the victory condition provinces at maximum and agree end the game then. Just my feeling.
Gem-wise, I was quite a paper tiger. This being the first game that got this far, I hadn't forged any gems or had any blood mages. Oh well, got quite a few from Oceania just recently.