Geometry originally built in Rhino, but I'm looking for help building it "better" with GH

Hi all,

I've been a Rhino user for a couple of years, but have only recently picked up GH. I've done quite a few tutorials, and am getting to grips with it bit by bit.

However, I've gone back to working on a project that has been left alone for a few months, when I couldn't get it just right and I'm finding myself thoroughly stumped. It was originally manually built in Rhino (see steps below) but I was hoping I could use GH to create better surfaces.

So, what I'm basically asking is if I can build this well using GH, and what approach I should use. It's basically a "c" shape, with a twisted octagonal surface of a varying diameter, but the files are attached.

I built this in Rhino using the following steps:

1. Drew my two outline curves, used tween curves to create a central line
2. Arrayed points at equal distances along the central curve, and drew perpendicular lines from these points to the outline curves
3. Created polygons (8 sided) using the line end points and added curve fillets
4. Manually rotated each polygon, by +15 degrees each time
5. Drew 2 edit point curves using opposite points on each polygon, connecting them all in a similar was to lofting
6. Used Sweep2, with the two twisted curves as the rails, and polygons as the cross sections
7. Extract isocurves, tweak, rebuild, use end polygon, split by isocurves, to sweep between each set of two isocurves
8. Tweak, rebuild, tweak, rebuild etc

My issue is that the surfaces this have produced can be a little tight/warped/loose/twisted/generally bad... And I was hoping someone on here could give me a little insight on how you'd approach this problem in GH. I know this is long, and rambling, but it someone could just point me in the right direction I'd be so grateful. I don't need a step-by-step, as I think it'd actually be good for me to figure it out by myself.

Thanks for taking the time to read all this! And any help is so appreciated!