Yeah, Redshift is pretty cool, and I hear it works with Blender. I bought Octane twice, and both times received refunds because the SketchUp plugin didn't work at all. The Cycles render is actually pretty good.

As often goes, people coming from one software to another most always have a difficult time adjusting. Blender 2.79 was particularly tough. I took copious notes using Google Keep so I could quickly reference them later.

Then came 2.8 and Blender finally decided to bring on board some real UI folks. The difference is amazing.

I've never been much a fan of Open Source, but I have to say Blender has yet to disappoint. My guess is you'll miss some features from Maya and 3DMax, but you'll have others. The non-destructive modeling workflow is just amazing.

Check out KIT-OPS.com for some really interesting kitbashing ideas.