The current nanomaterial recipe bugs me because it uses a different tier of each space resource, and because from a certain perspective, there is no reason why it needs to require the final tiers of astronomic, biological, and material science to be researched.

My proposed solution is to make the recipe take (along with the particle stream and thermofluid) one each of lattice-pressure vessels, self-sealing gel, dynamic emitters, and heavy assemblies, and to add an aeroframe bulkhead to the lattice-pressure vessel recipe.

I think the technology requirements can be justified as "understanding" the materials, plus it is part of the gateway to DSS. Moving it a little earlier for things like the turbines could prove interesting though, so I will look into it.
As for the materials, I think changing it to tier 3 of each sounds reasonable, will look into

Finally having a chance to check this properly -
The only 3 pre-DSS techs you can use nanomaterial on (without additional mods) are adaptive armour 5, and the big turbine/heat exchange. The armour needing T4 techs makes sense, and the turbine makes sense to need T4 of Astro, Energy, and Material... Maybe not Bio, but oh well. This means moving the tech around won't actually get the player any benefit, sadly

As for material costs - Recently the SE roadmap was updated, and 0.6 will be changing a bunch of material processing - I will hold off on some changes in my addon until 0.6 is finalised, to prevent confusion