Honestly a merge should include every nation. If the BBs don't want to merge the biggest nations that are already more than self-sustaining, then they need to make a cut-off of say 900 users for those that will/won't be merged. If that were to be the cut-off, 7 nations wouldn't merge with anyone. The other roughly 55% of users would be merged.
Merging nations changes the economy and competition of the whole game. Micro-merging isn't a micro issue only.
I would be interested to know if those micro-nations that have been named as possible mergers would be more open to the idea if macros were also slated to be merged?
I have 1757 players for sale and I'm $25,835,360 in debt. Buy them at outrageous prices, or be selfish and make me go bankrupt. You decide, BB.