I'd also like to see the pricetag for custom mapping to come down. Sure, it was meant as a money sink and players are rich af, but no one is really willing to pay 10m for a custom building or 250k per object mapped. I've had several conversations with players that would be willing to fork out 1 or 5 mil for custom mapping, but the general consensus is that
10m/250k is simply too much.
Perhaps combined with Miki's suggestion about having a place for players to make suggestions, there could also be a "Mapping Market". Players submit what they would like to have mapped for them or their group, how much they are willing to pay, and mappers from there can choose (with HQ approval, ofc) which projects they'd like to commission.
Multiple mappers could even compete to provide maps for the player/group to choose from and award the payment to. If not, then a tiered system, like 500k for a basic house, 1m for a regular size, 5m for mid to large and 10m for something gigantic-scale. Better yet, make gems useful and make them the required payment for custom mapping.