They could easily say - the system was designed for a fleet of 25 casual players - wait they have!!
So a 2 person fleet should take 13x as long as a 25 person casual fleet to reach tier 3
If they designed a 25 person fleet to reach tier 3 in 2 months that means a 2 person fleet should reach tier 3 in 13x 2 or 26 months - or about 2 years.
That is how the system was designed.
I will say this 100x if necessary - with the fleet vendor this is NOT a doff problem - the real problem in starbases for smaller fleets is Dilth and marks.
You need to realize one thing. Not every player in this game wants to be in a fleet or wants to be in a large fleet. I do have a couple of toons in larger fleets but that is those toons. I honestly prefer the smaller fleets to the larger ones I am a leader in. Fleets should scale by members.
1-5 toons: whatever works for that.
6-10 toons: double it.
Keep scaling the system in a fair way going all the way up to 500. No, that doesn't mean it has to double every time either. This system works on one principle. If someone quits, the system doesn't reduce the requirements to prevent people from leaving to make it easier. So numbers can always increase with requirements but would remaint he same even if half hte fleet quit.