Hi Pieter ,
thanks a lot for your feedback! It'd be very interesting for us to have a look at the project where you've noticed a performance drop to figure out, if it's really the texture resolution or something else. Would it be possible for you to share the project file with us?
I'd love to but I guess you guys will also need all the texture maps (it's a revit project). Unfortunately, afaik I will have to collect all the textures manually so it might take some time. I'll get to it asap.