2lz will be the person to really listen to, but for what its worth I have some experience off roading with a friend on a TT250. The reason tires is mentioned for more serious off road riding is because the TT250 tires are decently capable, they are still a 50/50 tire. The second you introduce them to mud or deeper sand they really start to struggle.
I do agree that gearing wise the TT250 comes just about perfect for a dual sport that will see some off road time with a 17 front and 50 rear.
I would recommend a skid plate, and as far as the pegs, yes, a set of wider ones will make you more stable when you stand. CSC actually sells both for the bike under their accessories section.
Some lever/brush guards would be a smart idea as well. Personally, I go for function over form and prefer the thick solid bar like these from Moose Racing.
https://www.revzilla.com/product/moo...xoCWZoQAvD_BwE
I can speak from personal experience that those things are strong as heck and will protect your hands from some pretty good impacts.
I could make a bunch of suggestions, but it really depends on how aggressive of an off road experience you are after.