Nice game!
Upgrading felt pretty rewarding, especially getting the first few.
When I was just mining my own business and saw different ores for the first time I actually got excited about it, because I wasn't anticipating it.
Very fitting graphics and a cool soundtrack (although it got repetitive somewhat quickly).
The only thing I didn't really like about the game was the scoring system. Felt like it was meant for a different game.
Especially with the upgrades and the best strategy being just to hold the up key without ever deviating to get the furthest wasn't that great.
The game is way more enjoyable when you aim to make money, instead of trying to get as far as possible. Especially because the upgrades for the minions don't do anything for getting a better score.