There's 3 things I see here.
First, Kahuna is right, if you are sitting at maxed resources most of the game then yes, you probably are either still learning the game or playing at a difficulty that is a bit low for you, at least in the early to mid game.
Which takes me to my second point, late game you should not be worrying about your economy. Late game is when you have gotten your empire as big as you are going to and are throwing everything you've got at the enemy homeworlds. So I do not support any sort of restriction on harvesters or income based on number of systems captured.
Lastly, I see everyone saying that they have so many resources that refleeting in trivial, then in other threads I see that unlocking Harvester upgrades is mandatory. Well, yes, if you've spent K to on economic unlocks to give you more resources then yes, you should have plenty of resources to go around, you spent the K for it rather then on a military upgrade of some sort.
I'm always hesitant to use my own games as examples because they are 10/10 games but I'm doing deep strike raids with starships (and so losing a few here and there) and I do not have excessive downtime waiting on the ships to rebuild. There is down time, true, but this is 10/10 so I'm taking it slow anyway. This is with no economic unlocks.
As for blobbing that started this whole thread, the major reason I blob is to provide shields for my bombers, not for the firepower. I'm quite willing to lose that cap of fighters to get half my cap of bombers home safely as opposed to the bombers not necessarily killing their target before dying if I send them in alone.
I'm seeing a lot of talk about tactical choices but with how mixed the AI forces are I don't think that's possible. In the defenders around that guard post, there is going to be an AI ship with attack bonuses against every ship you have so it's not worth my time to analyze the force composition, I'd rather just clear the system faster and have to fight fewer reinforcement waves.
You can make special structures, such as the Eyes, to counter the blob but at the most basic level I don't think you can remove blobbing from the game, there are simply too many units on screen to make it worth the time to command them separately.
D.