here are my first 3D models for the Colossus project
still need some work but getting there
may ahve to do some lower res tubes for doing whole bay with 100’s of tubes!
not certain yet of all the real tubes that ahve been use on the rebuilt Colossus
some might be Metal or Glass tube
You could cut down on the verts by using group instancing for those parts. Make that tube into its own group and use group instance. The down side is that you can’t array group instances, but the upside is that they don’t count as verts, edges or polys, only as objects. Or you can make the panels into groups and instance them as you need.
Duplicate group instances using additional geometry - subdivided plane e.g. - which you set to Duplicate from Faces.
Downside - you would increase vertex count by some verts and would need to manage positioning.
The tubes look great and I dig the shaders, especially of the glass tubes!
Like you I start to worry a bit about the polycount of the final model. Instancing would reduce the load of course and dupli faces or dupli verts would be an option, like ajm and eppo said.
Maybe the vertex count of each of the tubes themselves could be reduced a bit? 4K verts is more than I expected.
But I know that you spoke about low poly versions yourself.