This reads like an ad but I'm actually excited about it
I may be the last person to make this discovery, and that's fine, but if you've been looking for a new spot for 3D assets you can use as reference for your comic--why not check out MSPaint? They have pre-existing 3D models you can put together and edit, and you can also make your own. I haven't had time to really play around with making my own yet, but it might be a good (FREE) sketchup alternative, if you don't like making rooms in the sketchup browser.
Just open MSPaint, click on the "edit with paint 3D" button beside the colour palette, and start putting together 3D assets. It's so neat.