two stories
1) in 80 I ride from Paris to Dar es Salaam through deserts and West, central and East Africa. We were 3 at the beginning, with some tyres ( 2 ) . We were overloaded, ant sent back some stuff.
On laterite trails in Zaire, i felt too heavy with my zargal on the back ( at this time not so much material existing) .
So all you cand find do not take it tires, tubes (only one or mousse or reinforced ones or find a place to fix it everywhere mostly ), a few tools but ALWAYS a water filter .
You said no trails but you may find bad pavement, or have to cross rivers; or to push the bike ...

stay fit enough , able to run 50 meters , able to roll in case of falling maybe ?
I do some pratice training everyday , 15 or 30 minutes, and breathe
2) i rode Morocco trails ,some hard even too hard for me , NOT FOR the drz .
light weight is the way for all trails , on feet too .
Next time a GLoop coyote and tank bag will be enough for camping, and clothes ? Buy some if you need.
medecine ? minimum with basic oils .
photo gear ? none only a basic samsung stuff
gps ? basic C60
tent ? no a tarp