How to tackle the facility links?

So I’m around 20-30 hours into the game, just connected the timefall farm to the chiral network today and a bit confused about maxing out bases, which is something I really want to do both for the sense of accomplishment, the upgrades, the new trinkets and the important lore in the interviews.

So I already maxed out every facility in the eastern area but progress in central has been strange and a little confusing, for example I brought 2 premium deliveries to the farm, both of a similar magnitude (about 30 pieces of cargo in total) and while one got me from 2.5 stars to 3.3 or so stars, the second one got me from 3.3 to 3.4 if even that. Similar stuff with other prepers and facilities around, I get sidetracked quite a bit and end up doing quite a few standard deliveries, right now the engineer is the only one maxed out and the rest are all between 3.5 and 4.5 stars after gradual progress.

Should I continue gradually levelling them up as the story progresses? Should I focus on the more because of things like the disparity in how much some deliveries level up the link compared to others? Would like some advice