IMG gets 3x bonus on most mining, while houses get 4x bonus on the ores within their houses. The balance is perfectly fine.
As a person who has a dozen mining ships all over the place, I feel that all corporate mining ID bonuses are pretty well-balanced. Additionally, the profit from various fields are pretty well-balanced. Sure, silver from Humboldt is a great route. As a result, the field is always depleted. Sure, the Dublin gold fields aren't such a good route. But there are 6 fields, 3 of which have good bonuses, so when other fields are down, you can always trust Dublin to be fresh.
As for Miner ID, they need to have their bonuses raised to 2x. Seriously, because there's no point in making a mining ship for a 1.5x bonus, a person would be better off just using a big transport with a 1x rate and work for themselves, they'd hardly notice the difference.
Same goes for Molly ID. I believe their gold rate should be 2.5x. It's just way too low right now for them to even mine. Mollies are miners, they should be able to mine inRP, as well as just to give a bit of a job for molly pirate transports which might smuggle gold on their off-time. It won't be overpowered, you've already got BMM mining gold at 4x and IMG mining at 3x.
