Anyway, the question is "its worth the effort?" And I dont think so, for two reasons:
1. You cannot use the base like a regular starbase, for example, instead of Earth Spacedock or pre S-7 DS9, that was a tempting idea, specially for more "corporative" or roleplaying fleets. All the starbases are in fact the same one but with diferent instances, and not a real fleet home, its more like a starship bride, cause every time you came from a STF, PVE, PVP, etc., you spawn out of your base or from the point of the galaxy you transwarped to the starbase.
And it doenst have exchange. Lel. What a dumb design for a starbase.
2. Appart from some ships, you gain nothing really valuable for leveling the starbase. The fleet weapons are kinda crappy (DMGx3? Really?), the shields, well, the shields are good; but in general the lack of endgame content, or real PvP, or challenging PvE, makes not use at all of this "powerfull" fleet items. In this case, its the same problem as the Reputation system.
I'd add a personal third reason: Its boring as hell.
Our fleet decided long time ago not to put too many effort in the Starbase / Embassy. With those resources we are giving lockbox ships for our members, that are way better ships that the fleet ones.
Maybe if some day you can use the fleet starbase as your main starbase, and fleet endgame content is added (like sieges, fleet pvp, etc.), we would decide to make the effort, but for now, we want to stop in tier 4 military and wait to other things to do.