Seems kinda weak as a SA. It also seems to have the least synergy of any civ between SA and UU/UB. The Minuteman (combat bonus in friendly territory) doesn't play very well with this SA.
Well I wouldn't say it was a great ability, but its not awful, +1 sight for all units is definitely going to come in handy, as will "cheaper land grabs" if you want to spend your gold on that.
And I don't see how you have come to the conclusion that "The Minuteman (combat bonus in friendly territory) doesn't play very well with this UA"
(Its not SA but Unique Ability, ;p, i.e UA)
How exactly does "Cheaper and thus faster and more territory purchasing" Not help a Unit which excells in Friendly Territory, you will be buying more land and thus the minute man has more land with which it's ability has benefit from, this TIES DIRECTLY WITH THE UA. I really am flabagasted that you decided otherwise.