Missing pipes mk2 onwards

[ttr]

Hey,
I do recall there used to be higher tiers of pipes in past (copper, steel, stone etc).
Can we get them back? I do know that flow update did mess up how pipes work and i think this is why they where removed, but we do need them, otherwise, any upgrades like pumps, boilers, engines, reactors are sort-of pointless.

For example, if you do 2x5 nuclear plant (MK1) You're already maxing out pipe flow on water/steam each 11 heat exchanges, and you do already 14 water supply systems to keep up.
If you want to go to mk2, you can't do drop in replacement due to fact that pipes will limit to 1200 unit of fluid in them (and for longer pipes w/o pumps, even less).

Now, I do think fluid_box.height (or something like this) was responsible for ratio of flow for pipe