FWIW, most people seem to end up at 17/43. (Stock is 17/41)
This puts you in a nice sweet spot where you get significantly more usable gitalong, yet you can still bomb along the interstate serenely at 80+ mph.
I recall one guy who lived on a mountainous island, where interstate highways simply weren't a concern. He was quite happy with the much-increased poke of 16/43 gearing, and didn't care at all about anything above 70mph.
With 17/43 gearing, you'll have about 10.5%-11% total speedo error (gearing-caused error plus the 7% or 8% stock error). I found this annoying, so I added a SpeedoDRD. Some people don't mind the mental math involved and don't bother with the speedo correction.
2002 Suzuki DL1000 V-Strom, Dark Metallic Space Blue
1983 Suzuki GS850G, Cosmic Blue
2005 KLR685, Aztec Red - Turd II.2, the ReReTurdening