Yep. I'm planning to buy a Tikit for commuting and touring too. I already have a dahon folder which I7ve used for touring and it's very good. Someone asked why a Tikit and not a New World Tourist? The answer is that the Tikit ROLLS when folded. That means you don't have to carry the weight of it when you have to do long walks through airports and underground railway stations. This is a great advantage especially when you have a heavy rucsac or luggage to deal with.
No reason why you can't tour on a tikit as long as you keep your packing light. " panniers plus one other bag and small bar bag should work fine. Gearing? You'll walk up really steep hills anyway to avoid sweating and resonable hills can be dealt with by a modest gear range. My Dahon is only 8 speed but it gets up the hill well, low center of gravity and carries a load better than my mountain bike!
The best thing would be to fit an Alfine 11 speed hub gear on the back. That should do it. No derailleur hanging down or ground clearance problems. You are ALWAYS limited by small wheels. No getting around that and the NWT'S 20 inchers will give an advantage.
You might be able to fit 20 inch wheels on the front of a TIKIT with a different fork.
Lama fork? Don't know about the folding though but I'll bet Bike Friday can work something out for you.
The Tikit will be a great tourer/ commuter if you set it up right. You could also get the heavy rider upgrade for strength.

Good luck.