Running Hot?

Low speed only or hwy speeds?
Fwiw You might have a 4 blade fan and that would not be helping you at all at low speed and idle...so if that's the case, my advice is to get a 7 blade 'factory a/c equip cars had them' or just a good flex o lite that fits the shroud.

You had me until the flex fan...

I've seen and heard about flex fans coming apart... I would not use one...

Other than that, I agree with what you said...