Cores are random. I got 5 in my first one, then like 0 in the next 2, and didn't reach 10 for another 5+ mines. Then I hit another pair of motherloads and ended up with about 10 over what I needed. The infrequency of mines + the drop randomization is a recipe for frustration for at least 50% of the players.

The other side is that ML is back end loaded progression. The other biomes you grab some stuff and make things rapidly, but here, you can't make much until you can handle the mines, which is a mix of finding enough cores as above + learning the enemy + finding the darn mines + can't see the mines to find them.

assuming t4 on the items is coming, they will be much better than old gear eventually.