RE: Hot Weather Flying?
Getting more airflow across the ESC will help. A higher Amp-rated ESC should help as well.
If you mount the ESC on the outside of the fuse (power FET side up), right in the prop wash, that's about as good as you can get for air flow. A couple holes in the fuse and some double stick tape is all you need for that. There's a photo below of a foam plane I made with the ESC on the outside for cooling.
If you currently have power to spare, you could also consider a smaller or lower pitch prop to reduce the power a little, like say an APC 11x7E. I believe your stock prop is an Great Planes 11x8.5E, so an 11x7E will drop your power by about 18%. This is the cheapest & easiest option to try.
The higher amp ESC option will be pricey, so I'd save that option for last.