Sub surface hard points seems pretty pretty useless though.
I personally don't take with me anymore, just seismic, abrasive and laser.
But indeed, motherlode mining is a great fun even without the void opal price tag.
TBH this is telling of the current poor balancing of the mechanics. It should not be designed so motherlodes are basically the be all and end of mining. All types should be rewarding (CR wise), all the way up from legacy mining to motherlodes, simply with motherlodes being a nice surprise (icing on the cake).
At the moment, the PWA, with its "here is the new gameplay" behaviour, and the entire payout balancing structures seems to almost be 180 degees out of wack. Legacy mining and surface deposits should give a nice income. Sub surface and especially motherlodes should then be a rewarding addition, not the goto game loop!
The PWA creates a needless break and balancing issue between legacy and new mining. With FD then over compensating with motherlodes to make new mining financially rewarding.