If you like the SV, get the SV.
Take the MSF course if you haven't already, and get on with the learning.
My return to Motorcycling bike was an ST1300, after being gone for 20+ years.
I race(d) an -01 SV650, and loved the bike. Same power characteristics as my ST, and a bulletproof engine. Suspension was reworked on mine, and mine had braided lines and EBC -HH brakes. It stopped fine on the track.
As far as the SV keeping up on the interstate...
I liked the SV's engine enough that I bought a DL650. Same engine, detuned a bit, with a DS frame/look. I cruise at 75 on the Mass Pike at about 5500rpm, and still have enough power to spare to pass when necessary. The ST does it more effortlessly, but there's still enough to get going.
One poster mentioned Sport Touring the bike. I think the ergos would tire one out, but people tour on many bikes. That's a choice you'd have to make.