I've thought a little bit about the magic site issue and came up with a couple arguments against increasing it:
1. It decreases the value of a luck scale. More gems from sites means that the gems from random events make up a smaller proportion of your gem income.
2. It makes blood nations more powerful. The trade off for blood hunting is the gold cost from unrest + upkeep of blood hunters. With increased magic sites you get more blood slaves for the same gold cost.
I'm playing a blood nation that likes luck scales so it's hard to decide which magic site setting I prefer
. Just put me down as "neutral" if you're keeping track of player preferences.