Pawleyk, those are some nice looking models!
You're really far down the sketchup path so this might be too little too late but Solid Edge has software that is very comparable to Solidworks and they offer a subscription model. I've used it a few times. You download the full piece of software to your machine and then can use it offline. Still pretty pricey though compared to sketchup but it seems like a pretty good way for a non-professional to get a hand on commercial-grade CAD software
https://www.plm.automation.siemens.com/store/en-us/solid-edge/index.html
You're really far down the sketchup path so this might be too little too late but Solid Edge has software that is very comparable to Solidworks and they offer a subscription model. I've used it a few times. You download the full piece of software to your machine and then can use it offline. Still pretty pricey though compared to sketchup but it seems like a pretty good way for a non-professional to get a hand on commercial-grade CAD software
https://www.plm.automation.siemens.com/store/en-us/solid-edge/index.html