Easy way:
Only 2 permits per planet, but both give 500 area. So 1000 area is still the max.
Elaborated way (the basic idea is from an older post):
No permits. Max area per planet 1000. New player starting with 1500 area.
Each HQ-Upgrade grants 500 additional area, that can be freely distributed across all your planets via buildings. That allows a vast customization of base sizes and favors out-maxing as long term objective.
Starting a new base takes only 25 area for the Core Module.
Maybe a Base-count-cap is needed: initial 3 bases. From HQ-Lvl 4 and on +1 base per Lvl.
That means:
Lvl 1 - 1.5k area can be distributed across 3 planets
Lvl 4 - 3k area, 4 planets
Lvl 10 - 6k area, 10 planets
Lvl 20 - 11k area, 20 planets
Qiro o7