Trust me when I say many many devs fully agree that Discovery has too many bases and too many systems, and I've tried hard to encourage people not to make new bases without a purpose, or bases that are redundant. All new bases need unique backgrounds, unique lore, their own trade routes set up for them (making sure those bases receive traderoutes is part of the system dev's job as well as the trade system's. They need to work together, but unfortunately some system devs have just dropped new systems onto the trade system's lap and said "give me routes").
Gallia's massive amount of bases and new systems were not added in by the dev team, but by the mod lead, Igiss. And I know many people who think it was a very bad way to go with Gallia, spreading out the systems so much that player interaction will be hurt by it.
That about summarizes my opinion on the size and quantity of Discovery's systems and bases.