Bear with me as I won't be giving a very in depth rate, since don't play sun very much.
You should probably use Heat Rock over Wide Lens on Exeggutor because you usaully won't be using Sleep Powder more than a few times in a match. From my experience with weather teams, having three Heat Rock users is very useful, especially when two of them are sweepers that will be likely staying in for a long time.
Probopass should be using a Specially Defensive Spread since your main goal is to last as long as possible to set up Stealth Rocks and Sunny Day. This team doesn't need the extra power those Special Attack EVs bring.