I agree with what seems the consensus in that the main issue is stuff just isn't communicated as clearly as it could be, which you're obviously aware of and already said you're fixing, which is great. I still don't know if the blue ores give more than the normal rocks but i still go for them because well, why not.
The strategy i landed on was also pretty formulaic and the game could really do with something there to prevent me from just turning my brain off and doing the same thing every time: Get all the red ores to pump up the multiplier as soon as possible, use my horizontal and explosive strikes to target either as many ores as possible or the most rocks that are close to breaking, break every 2 i see with my normal pick until i run out, then break 1's with the weak pick until i run out.
Personally i'd have loved to see a second scene with the slimegirl after buying every upgrade, but that's additional art and so would've eaten into development time.
Regardless she is very cute and i appreciate the option to turn off the cosmetic upgrades, though i only did that with the tits.