There is a massive difference between "balance changes" of a post 1.0 environment and the changes from early alpha to 1.0.
Here we disagree. Devs stated their intention to keep developing the game after 1.0, just at slower and more careful pace (less features and more polishing). But it will be gradual process, not hard transition.
Same could be applied to all mentioned methods of discouraging hoarding. They could be more drastic now (i.e. 5% inflation per week) and milder over time (1% close to full release)
Already end of closed alpha showed us how approaching wipe affects player population: everyone (except SSC hermits) stopped playing, knowing that all they'll do will be soon wiped.
Maybe have player stations also have some upkeep to them?
Player stations (outside of SZ) have a natural upkeep: you need to defend them, repair after battles, refuel generators, ect. Those inside SZ should just count into the basic limits.
Monetary upkeep is not an option - so far all the money sinks and sources were strictly tied to dev stations. Money can be exchanged anywhere, but created and destroyed only at Origins. And IMO that should stay.
Upkeep could be some kind of fuel used to preserve ownership of the station, and to keep the offline protection up. I.e. it could chug exorium proportionally to stored assets. But is it really needed?
After enough time, left unchecked, a one-way and non-reversible steady inflation would see a stack of bastium worth 10mil. That's just insane.
Numbers are just numbers. You add k/m/g to the end, and zeros are not a problem any more. Or just make devaluation from time to time.
Alternatively you could just evaporate % of money from time to time (call bank fee, or something).
And/or allow spawning credits in physical form: money chips. That would allow having more money than bank limit, or allow avoiding bank fees (when kept outside of SZ)
There need to be some system that discourage hoarding excess money in absolutely safe environment.