[Dimaz]

The game that Xanatos (IIRC) tried to start with CBM 1.5 short after the 1.6 release never started because there were only 4 or 5 players who wanted to join (including me). I think that shows the level of acceptance. I know some people that were against the change but it was sort of impossible to start the game with gemgens here at the time.
Blood being op is completely different matter than SDRs being gemgens or not. Actually I'm not sure that it needs external balancing even if it is op as usually it more or less balances itself in the game (especially with diplomacy). Also banning gemgens effectively made blood stronger so it's just the conseqence of previous decisions. And removing SDRs of cause nerfs blood but 1) unequally for different nations 2) it removes just another "investment" part of the game which is bad imo. They are sort of cheap for what they do I agree, 10B seems more adequate.