Hemza

I feel that 40 minerals every minute is great for the higher tier ores. Say iron ore sells for 4.1 credits a piece. The mine cost 100,000 credits. That means to make your money back on the iron mine you would need exactly 24,390 iron. This takes 609 minutes (10.4 Hours) of game play time. By that time most people have moved on to other ores. I feel that the ore output for iron should be higher to be a viable cost effective option in the early game.