Agree, on both issues.
Temperature should be mid-range for most all fish ["range" here being what is given in our profile for the species]. The upper and lower extremes are what the fish can usually tolerate, but should not be subjected to long-term. The reason is that the higher the temperature, the harder the fish has to work just to exist. This wears the fish down, uses a lot of energy, and this can lead to weakening of the immune system, poorer health, increased disease issues, and a shorter life.
With angelfish, the wild caught fish must, like discus, have warmth, and 80-82F is minimum. But the angelfish you buy in stores will almost certainly be tank-raised and these do not need such warmth; they are fine at "normal" tropical community tank temperatures areound 77-78F.
So, I would for this reason not add the common ram, Mikrogeophagus ramirezi. Its cousin, M. altispinosus (Bolivian Ram) wouldf be a better choice. The angelfish will be healthier at this temperature.
Byron.