You_Fool wrote:so actual Imperial Savings and Loan?
Why not? Well, say there was a galactic bank where all the defense station savings from all fams were kept. A fam could borrow money from it at a certain annual interest rate, payments automatically made every tic in the form of increased 'decay' rate on the all fam members' GC, resources, units, etc..
The galactic bank could use all 'decayed' GC, resources, and units, placing units on market for auction, resources on the commodity market. The holdings held by the Galactic bank would determine the interest rates for players to borrow GC.
The current 'decay rate' could be changed to be called simply 'tax', used to fund the Tokassi empire.
Fams could opt to stop paying taxes and thus not have a decay rate, but only if they declare war on the Tokassi. 
In terms of the code for how the bank would be paid back, it would have to be set up so that if one member of a fam, say an attacker, were running a negative income, the other members' decay rates or 'payments' to the galactic bank would be increased accordingly.
Therefore, 'decay' of GC and resources would have two components: the 'tax' that is collected by the Toakassi empire, and secondly the amount of 'tickly' minimum payments family's are paying to the bank for borrowing GCs.
If a fam ends up unable to pay the minimum payment (such as in the event all members of the fam were running a negative income) the fam would be forced to declare bankruptcy, could not borrow from the bank anymore, and fam's infra (all members equally) would automatically sold at a value of 70% the 0% OB cost so as to repay the bank loan in full.
If a fam no longer had enough infra to repay the loan in full, planets would be sold to the galactic bank and sold at auction to highest bidding fam.
If fam didn't have enough planets to be auctioned off, of course all their planets would be sold at auction and the fam would be destroyed.
Now, throughout all of this, interest rates on amounts borrowed would vary according to the galactic bank's holdings.
Only the fam leader could decide when to borrow money or when to make lump sum payments.