I'm sure someone here can offer some suggestions on the heating issue but from your mods list, looks like you've taken the steps needed. Maybe a different fan or clutch, something with greater cfm. Is your radiator 2 core? I'm guessing it is... Or try getting larger intercoolers or maybe some kind of water/chemical mix injection system. Love those videos...better than NASCAR since I like the car in your vids!
Nissan.....Euro Oil cooler system (Genuin Nissan parts) ARC.....All Aluminum Racing Radiator Nismo.....Racing Radiator Cap Nismo.....Low Temp Thermostat