I'd add surface exploration mechanics, just some sort of process whereby a planet's surface can be explored that would provide a reason to spend extended periods scouring a planet's surface beyond surveying nodes, and that would generate data sellable to UC that would have a comparable time:value ratio to jump\honk\jump\honk exploration (if the rock itself is valuable enough). Not looking for something that would make me rich, or would be so lucrative that explorers would feel they were losing out on money if they didn't cart an SRV along. All I'd really want out of it would be for planetary landings to not halt exploration income.
It would be fantastic if such a mechanic encouraged exploring multiple landing sites, exploration of canyons, diving into super large craters, etc etc.