For those who does both tracking and mixing

What’s the recommended way to mix after tracking/arranging with VST?

I currently have 30+ VST instruments loaded with about 100 tracks. And right now, the project is quite laggy due to the VSTis being quite heavy on CPU.

One option would be exporting instrument tracks via mixdown and import them into a separate new project, or just using the render in place function and do all the mixing in the same project file and freezing the instrument tracks. I guess whichever would work, but would like to know how others typically go about this.

I render in place sometimes saving the entire plugin chain. I always do a save as and make another project before I commit to something, but usually I am ok with committing to something and I’m still able to eq if I need to. I only have a i7 930 processor though so I’m about 10 years behind on CPUs.