Yes, they can be very intense! Some are just absolutely gorgeous though… Cathedral landscapes is a good compromise, I think it possibly even beats vanilla in some regions when it comes to performance.

Yes you have to generate a grass cache and run TexGen and run Dyndolod all of which produce output based on your specific load order so it is something you would normally do when it is “finalised”. My problem is that as soon as I “finalise” a modlist I get a craving for Vanilla, maybe with just a few fixes, and maybe a lighting mod, and maybe…