100%
A great stock JCM800/JMP 2204/2204 is a excellent start, it's the benchmark of all modelers in my personal opinion, every company should have the best sounding 2203/2204 reference amp (or two) they can find then model it to the best of their abilities.
Then do the same with stock 1959, 1987x and Jubilee for a solid Marshall foundation in your modeler.
#34, Jose, et al will be very nice additions too.
Do the same with Mesa amps, model all the channels and switches of great sounding IIC+, IV and Rectifiers you can find and afford.
This is where Fractal stands out, they already have all the above, plus advanced tweakability one like me would want to fiddle with.
We finally have an official Fractal dealer where I live and I am very tempted to splurge.