Welcome Steve,
1. Use the AC for temps above 82f, you will get a small hit to FE but it will keep the battery comfy. Set the temp to 75 and place it on auto.
2. EV is a big bang for the buck. Use it up completely when you know you will be getting on the highway soon to recharge at higher speeds. If your battery has to recharge from empty while you are stopped in traffic, it will be a bigger hit than you like.
Good Luck