Quit whining.
Also, OP. Get over it. Just play the damn game and stop trying to change it to suit your needs.
It's already bad enough that three people are fighting one guy.
Keeping factories while growing is a bad idea. They're good for big periods of growth though.
Foreign Ministry/Factories/Harbours though for the first rush of tech deals.
Then changing to banks and such.
So did you just leave without wrapping up the state of affairs? Or is it the end of your term in government?
Leaving an alliance, especially when you're a member of government, on a whim is something that's frowned upon.
That's your speculation, that the $$ added by gems isn't multiplied by improvements. Personally, I think it is.
Unless you have definative proof that it doesn't, you're talking nonsense.