Rohloff systems offer 526 percent.
I recently commented on another thread that I am quite happy with an 8 speed cassette (Sram 11/32) for a derailleur system. With my road triple with an aftermarket 24 tooth granny gear (52/42/24) I have a 630 percent range of gearing, which is so wide it provides even a couple gears that only get used for strong tailwinds or for long shallow downhills. On each chainring I do not use the two gears that are the most cross-chained, in other words I only use 6 rear cogs with each chainring. Thus, my chainline stays in a reasonable range, although that means I settle for 18 gears instead of all 24. Several of the 6 gears that I do not use are redundant anyway, so, no real loss.
For touring, 420 percent could work for some but I like a wider range myself. Some of the people that really like Rohloffs like them because there is only one shifter. Thus, it is very simple to figure out how to upshift or downshift and they can easily find all gears without any confusion. The 1X11 system would offer this same benefit - which I am sure is another selling point.
I think some have been using single chainring bikes for cyclocross. I would not be surprised if the 1X11 system gets used a lot in cyclocross.
Instead of a chain keeper, a bash guard both inside and outside of the chain would work and keep some peoples pants cleaner. This would use long chain ring bolts and spacers for third position on a double crank. My Airnimal Joey foldup bike came with two bashguards attached this way.
