I've got a 48 hr SN BZ save, already mined koppa site out
Set up your main base in the thermal spires, near delta island, purple vents, and twisty bridges
The lilypads isn't great, building beneath 200m is too constricting
The purple vents are meh, decent power but too many cryptosuchuses and crash fish is a large problem
Don't even think about the tree spires or the twisty bridges, they're way too dangerous
Try to build bases with MPRs in the beginning (read: before you can scan a large room), outfit them with bioreactors. If you have filtration plants, use nuclear reactors or solar panels, since 1 bioreactor can supplement 3 MPRs and a moon pool at constant max capacity.
For the crystal caves, I don't recommend building near the tree spires entrance, its even worse than the purple vents entrance, and to fit a seatruck dock it needs to be in open waters, which should be about 430m deep or so
An excellent method to supply power to a major base that you want to keep spacious is to build a foundation on the surface, stuff it with solar panels, then build transmitters. Gold isn't a problem if you went in Koppa.
Speaking of which, set a base up just above the koppa ravine. A seatruck dock would be nice but inessential, but a moon pool for a prawn is required.