I agree. As much as I love this game, one of the biggest gripes I have is that there doesn't seem to be any real drive to actually get stuff done other than the desire to unlock higher tiers. There isn't anything to do with the stuff that you make.
Most of the enjoyment of this game comes from a sort of "make your own fun" point of view, where you come up with a project and spend your time working on that. And don't get me wrong, I've spent tons of hours just doing that and enjoyed it completely. I just wish there was the option to have more of a incentive.
I've stated a while ago that coal power is too OP. And I'd like to extend that to fuel as well (I haven't gotten to nuclear yet, but the waste seems to be a nice counterbalance, on paper) Just the other day I plopped down 5 fuel generators because my truck delivery was bringing in too much fuel and it was clogging up my inputs. I was trying to burn through it faster because there was nothing else to use it on. But even after I built 5 generators and overclocked all of them, I was only burning through fuel at about 2 seconds faster than before. Barely enough to address the issue I was having.
I feel that there should be gameplay incentives, other than the desire to unlock new stuff, that encourage you to keep playing. Some (non-essential) machines that require some upkeep that involves the production of some materials. This would give you something to work on automating and also give you an opportunity to sink the production into.