So I had this idea a little while ago and I don't know if this has ever been said by devs (or at least I haven't heard about it, so please lmk if it has ever been adressed) but I feel like it would be a pretty neat adition to ksp2, where the tech tree is unlocked partly by science and partly by resources. It has been said in the past that KSP2 on full release will be based around resources, not money, and that got me thinking that maybe it'd be cool to have them not only be a way to manufacture and replenish your crafts, but also making them unlock new tiers in the tech tree. Idk how resources will be implemented when they do (whether it be a single "resource" meter that drains, or many different minerals and compounds that each have their own gauges), but the way I think of this, it balances out acquiring busted tech by forcing you to acquire a certain something that is somewhere in particular, making it more like a "mission to be able to progress" rather than a shopping list. A more clear example would be, for instance, that in order to get something like the terrier engine, which usually is a big part of interplanetary travel for small vessels, you need to get a certain ammount of mun rocks and science points, or some mineral from mun's surface, meaning if you want to progress considerably, you need to achieve a mun landing first. (Idk i'm no game designer so the balance is up to intercept, not me, but you get the idea)
In ksp1 you could literally just have one of the big labs in LKO and refill it with whatever science you got pretty much anywhere in kerbin's SOI and with enough time that'd be enough for most of the tech tree, so with something like this it could help combat that and allow for more "coherent" technology, but that's just me though, what does everyone else think?