Would it be possible to implement a feature to queue up a list of parts to change in the parts selector and then just confirm the changes at the end? It's pretty annoying and tedious to scroll through the parts selector over and over again while being interrupted by the whole vehicle being reloaded after changing a single part. I believe that this would make the process of modifying your car a lot less painful and much faster.
This can be done to some extent by pausing, (which is what i currently do) but only allows selecting parts available at the current level eg. Changing from a 17x8 to an 18x10 wheel, I can't then choose what size tyre i want to use for the 18" wheel until I have unpaused and the car has reloaded. So yes, this is a feature I would greatly like to see implemented.
Too bad there's yet to be any feedback from the devs about this so I guess we're just stuck waiting for now ¯\_(ツ)_/¯
Even with rewritten and updated menus, that would be logical to happen in a future, this feature would most likely be very useful.
I think that even with greatly reduced loading times this would prove to be useful as a way of making the whole process more seamless.