2. I think the number of kills count.
Thats cant be the only influence.
i got a 3 stars private whos got 80 mission and 90 kills and a major with not 50 of each of both.
yeah 28, 2 x 8 team and 1 heracles.
some missions i won in first round, each soldier can shot 2 times and there are not more than 24 aliens in an open field mission
not the problem after 300+ missions played without any skilled soldier died in the medium difficulty.
i researched the bomber, but the mission was lame.
i meant a base like "tleth" or however it was called in the xcom versions.