I’ve gotta say weldment is the right tool for this, in my experience. Maybe some steps aren’t set up right? The Weldments feature in SolidWorks is tuned for tubular structures like yours. Define profiles for all tubes, and use the Structural Member tool to create your frame. This automates trimming intersecting tubes, so this should capture most of your normalization.

For intersections at odd angles, you should create reference planes at the cut angles. Use these to make precise cuts, consistent across similar joints.

Also, build a 3D sketch for your layout. This visualizes intersections better and ensures angular and dimensional accuracy. You can adjust this without influencing profiles or intersections. Where tubes intersect at odd angles, the Trim/Extend tool with the Miter option can help create accurate trims. This can manage mismatched tube types.

If adjustments are needed, use Cut-List Properties to normalize lengths and specify angles. This helps in adjusting cuts and keeping an organized parts list.

Also exploring symmetry and mirror sections rather than doing it all the long way. After you’re done normalizing cuts, use the Interference Detection tool to check for fit and eliminate overlaps.

We made a few articles on designing normal to surface cuts in tubes, which you should check out! The one that gets slightly tricky is miter on round tube. I’m a big fan of delete face and thicken for most other cuts.

1. Normal to Surface Cuts in Tube Manufacturing
2. Designing Normalized Coped Cuts on Round Tube
3. Designing Normalized Mitered Cuts on Round Tube
4. Designing Normalized Mitered Cuts on Rectangle Tube