So, I decided to try CoT3.1 w/ RLO in lieu of RCRN, which I had been using. So far, so good. I am using CoT Winter & Nights Level 5 & Sounds then RLO interiors/dungeons. I have CoT below SFO - did not try it the other way. Just used BOSS and let it do its thing as far as .esp order.
Looked at CoT 3.1 a bit. (I installed all the defaults.) The only mod it seems to overwrite is a texture for tundragrass from Skyrim Flora Overhaul. (I removed Immersive Thunder as that seemed too big of a conflict as I assumed the .esps would not play not. Plus I want to try out the Cot Sounds.)
I use CoT 3.0 and RLO 4.0.7c atm... with my own custom ENB.
(Remember that CoT is incompatible with a few mods on the SR list like dramatic clouds.)
Dramatic clouds has textures but no .esp. The textures do not conflict with CoT 3.1. The note about a conflict a few months ago mentioned that whichever cloud texture you preferred should just overwrite the other.
CoT winter seems to overwrite a few SFO (farm house and dirt) and World Map items.
I wonder where to put CoT in the process. If it's before textures I will get to keep SFO's tundragrass, otherwise I will get CoT's. CoT Winter (if I use it) should go after SFO so I get the new snowy goodness.
BOSS seems to have the esps all sorted out.
I'm kind of shocked that MO does not list any conflicts for RLO or or Skyrim Project Optimization. I guess this means their order doesn't matter so long as I let BOSS sort out the esps.
Only reason I messed around with this is because I broke my previous save with RCRN :( I swear I just need to leave well enough alone at some point haha!