How much riding do you do each week? What do you consider a "long" ride? Better conditioning or a lighter/more aerodynamic helmet might be all you need to be more comfortable... I've owned a couple of touring-capable bikes over the last ten years and noticed that if you try to go directly from riding the couch to riding 400+-mile days you're going to be hurting no matter what machine you're on!
All good points. Though I don't think a Street Triple is a promising bike for most older riders to ride all day, day after day.
As an older guy with neck and back issues, I did need to change helmets to manage neck pain, and also stop using helmet mounted camera.
There are bikes I feel the distance less than others on. For example I never remember feeling it at all on my Versys. But I was commuting regularly.
A look through barn door screen isn't a terrible thing--except in appearance, and cross winds. And it has an advantage in the evening when the clouds of bugs appear. Better splattered on the windscreen than faceshield or teeth. I probably won't use one again, but the OP might like it.
For me anyway, a small screen seems like enough. As long as the helmet has a decent wind profile, wind itself doesn't seem terrible, though with the wrong screen setup, buffeting can be.
I've used an MRA touring screen like discussed above on a bike before, and it worked great for me without the flap at the top. I figured if I needed more I'd add the adjustable flap. But I didn't. The MRA X-creen can be added to the top of many windscreens.
I still think a different bike is a better bet though.