I have a 2019 XR and a 2016 R1200RS. I've also recently had a Yamaha Tracer 900GT and a KtM Super Duke R.
The R1200RS has more HP than the S1000XR up to about 6000 or 7000 rpm's, then the RS dies around 8500 rpm and the XR just keeps going to 165 HP at 11k rpm. I find the R1200RS boxer to be completely satisfying in HP on everyday road situations, whether it's 30 mph passes on the mountain canyon roads, or 70 mph passing on the Interstate highways. But, (there is always a but), the RS engine doesn't seem to be happy past 7000 rpm, and the XR just feels stronger and smoother as the rpm's build up.
The clutch on the XR sucks. The quick shifter on the XR is superb and salvages the ugly clutch. The XR sits high, 33"
The KTM 1290 is a great engine, but you said you don't like twins, so much for that. In every other way, it's a match for XR. I had the Super Duke R and not the GT. If I had had the GT, I might still have it.
The Yamaha Tracer 900 GT feels like a smaller, simpler, weaker XR. They have many similarities in ergonomics and feel. That 900 triple is a great motor, it feels very strong 90% of the time. But not 100% of the time and I wanted 100%. I traded in the Yamaha and the KTM for the XR and I am quite happy with my choice.
I find the Kawasaki 1000 Versys very interesting, but it's about 50 lbs heavier than the XR and I don't like its looks.
A Yamaha V-Max is on my bucket list, I wish we could trade bikes for a week!