Do faired recumbents need more gear range?
Short answer: yes, but a Rohloff works for me.

I've been riding a Rohloff-equipped RotoVelo on and off for a couple of years now. I did play with the gearing a little when I got it and it's pretty usable now. The RotoVelo weighs about 33kg and I live in a relatively flat city.

I have it set up so that spinning reasonably fast in bottom gear I'm doing about walking speed - say 3km/hr. That way I can go up overpasses and the sort of hills we get in Melbourne and Sydney with a bit of work. Set up that way I spin out at about 80kph. Frankly, at 80kph I've usually stopped pedaling and I'm just going "wheeeeee!". My top speed ever is over 100kph, which was a bit scary.

When I stop at a traffic light I shift all the way down then back up a couple. And I mean all the way down, typically at 30-40kph cruise speed I'm in gear 9 or higher, so it's much easier to just twist all the way than try to remember what gear I'm in. Which is an advantage of the Rohloff - all the gear intervals are the same so you can just keep shifting without worrying.

It's possible to combine a Rohloff with a front derailleur if you really need to. I suggest waiting until you have the velo before committing, but make sure you can if you need to - most velo makers normally ship deraillers, so getting them to leave the front derailleur post in place shouldn't be an issue. With your small rear wheel (most velos are 406/20") the low gear should be fine with the Rohloff 2.1x gearing requirement, it'll be a question of how big a chainring you can fit in.

For touring I'd be tempted to use lower ratios than for commuting. With heavy gear in the bike and more hills in the country I found that I was pushing the velo more often than I would prefer. Partly that's from the heat build - lack of ventilation becomes an issue when you have to work really hard to keep the vehicle moving at all up a hill. Not being able to pedal faster than (say) 60kph wouldn't bother me, but being able to sit back and grind slowly up long hills would be better than pushing.