Lots of possibilities: Conti Ultragatorskins at 1.125 inches, Sport Contacts at 1.3 inches, or if you want something with a beefier tread, there are Schwalbe Marathons at 1.5 inches. All seem to me to be pretty reasonable and sensible choices, depending on what sort of touring you're doing.
Yes, I have to agree. The number of 700c touring tyres seems to give the impression that it has reduced a little over the year (depending upon whether or not you count winter tyres/audax tyres/commuting tyres/etc as touring tyres). There's still a good number around the 28mm mark but for those of us that want something a little wider the possibilities decrease a little.
Whereas the 26" 'touring' tyres seem to be increasing. OK, these might not be designed predominently as touring tyres, but they are by default wider than the average 700c jobbie ('cos they have to fit people's pre-existing MTB rims in place of knobblies) and have all the comfort and toughness associated with touring tyres (IMHO).
Are there as many viable 26" touring tyres as there are >28mm 700c touring tyres? I don't know but if there aren't then the gap is reducing.
For my part I used 26" IRC Metros for my LEJOG in the early '90s - very limitted choice back then. I found that they rolled extremely well - at least as well as the touring contis on my 700c bike, plus they were more p*nct*re resistent. Furthermore, one of them is still going strong on my commuter! These days I have Marathon Plus on the 26" tourer - used on road, for audax, for club runes, on track and BWs. I'm perfectly happy with them. Not as fast as my GP3000s but if I wanna go fast I switch bikes.