Lovely scene, it's understandable to have long render times with this much detail. A fair trade, if I may say so.
Vue gave me that impression too when I saw Vue 8 or 9 the first time tbh. Too many upgrades, little added value. Same goes for Autodesk tools, unfortunately. Aside from the unacceptable prices they set (~4000 Euros) they release a new version every year and upgrading still costs around 2500 Euros and it doesn't even worth upgrading. To top of that you can't upgrade if your software is more than 3 years old. That's pretty annoying to say the least. I'm not even mentioning horrendous 1800 Euro yearly subscription.
Anyway, I still like Autodesk software and not upgrading is not end of the world. Just because your software is getting old doesn't mean it will be out of date like that. I say no to unnecessary spending.
I think you should stick to Vue 10, too. If you're comfortable, there is no reason to change it. You are doing well with it obviously and also you can always buy Vue 17 a few years later for your newer work