To make things more realistic, there should be a fleet tender ship type. The following aspects to this fleet
1. No attack capacity (no weapons)
2. Fleet tender ages and must return to base to replenish. Fleet tenders when in use have a specific draw down of support from lets say 100% to 0 in increments of 2% every 24. This would be more realistic because as supplies are consumed they have to come from somewhere.
3. All fleets require at least one fleet tender for extended operations. Any fleet without tenders can operate 7 days off base and must return before the 7th day or the fleet will be stranded. Large fleets above a certain size must have 1 fleet tender per credit value. Lets say for sake of argument that the number is 1 tender for every 50K credit value of fleet. If a major fleet has a loss of fleet tenders, this leaves the player 1 week to return back to home bases for replenishment. Or conversely they stranded fleet can be rescued by fresh tenders
4. Fleet stranded for more than 2 weeks will disappear.
4. Fleet without fleet tenders can move if within the 7 day period launched from players empire bases, but has the same limit on time of operation as a fleet with fleet tenders that lose the tenders. Fleet moved without tenders will be left stranded if off base from players own bases if not returned back to base before the week. Fleet can be rescued by sending fresh tenders.
5. Fleet in vacation mode must be moved back to base. If the fleet gets sniped and loses its tenders while in VM mode offbase, the fleet will disappear in 7 days if no action is taken. Fleet over home bases of the player is preserved irrespective of fleet tenders.
6. Fleet without tenders has a 7 day clock invoked to notify player of loss of fleet at end of time. If tenders arrive within that 7 day window, it will take 24 hours to fully recharge the clock.
This is in place of fleet maintenance. And this new ship type could be implemented in all servers.