I wear an R3 as well. Just like you said, as long as I'm moving i stay comfortable at high temps. I find the venting adequate.Regarding riding in different temperatures, everyone is different in what they are comfy with and I have learned that as I age what was comfy before isn't as much now.
Being over 60 I have found I don't have as much tolerance for being too hot or too cold than what I used to when I was much younger.
For hot temperatures I wear shorts and a T-shirt or a normal cotton shirt. I wear an evaporative cooling vest on top of the street clothes. (The vest gets wetted when I stop for gas.) My Roadcrafter R3 goes over that with the underarm and back vents open, the sleeve zippers open, the main zipper down a little bit (depending on how much flow I need.) The zippers that go to my street pants-pockets open and the pant zippers not fully zipped (but the pant cuffs snapped together at the boots.) This has worked for me keeping me comfy in up to 100°f/ 38°c temperatures on trips and on shortish rides on city streets.
I haven't commuted in those temperatures. When stopping the Roadcrafter goes off so quickly that I am almost instantly in my shorts and T and just have to take off my boots and socks and put on my sandals.
I found that the most important thing for me as I got into my 50's and now 60's was to Hydrate. Not just water, but make sure I had electrolytes. In my tank bag I have a bottle of water with "Nunn" hydrating tables in it so I get the same effect as Gatorade but without the sugar. I can flip up my helmet at almost any speed and take a drink.
I wear the same Roadcrafter down to 0°f / -18c and just put layers under it but over my street clothing. ("Warm N Safe" heated jacket and softshell over cotton shirt and normal street pants take me down to 32f / 0°c.)
Up until recently my R3 has proven to be waterproof. Lately I am getting the dreaded wet crotch in solid rain so have to figure out what is going on there.
I had some cheapo crap before this but haven't tried the other big name stuff. The Aerostich factory is only 90 minutes away so it seemed like a natural to buy local.
Keeps me dry too. Its only 3 yrs old. I've ridden for days in the rain and nary a drop inside. Ok. Maybe a drop or two down my neck when i lean out to clear my visor.
Not saying it's the best for everyone but it is the best for me.
Relax and have a homebrew.