Hi all

I have the next several months to get some serious bikepacking done. I have a rigid steel 27.5+/29er MTB. It came stock with Tubeless ready WTB Trailblazers 2.8". I was planning on putting in some sealant and using these for the GDMBR. Later I'm off to Oman to cycle around there before doing the Dragon's Spine in South Africa (as seen on bikepacking.com). In Oman I am expecting a hell of a lot of pavement riding but with a fair chunk of unpaved too. The route in SA is all off-pavement and people have recommended tubeless on account of the goatsheads etc. So I'm wondering, should I fly out to Oman with some standard Schwalbe touring tires like the Marathon MTB etc, but take a pair of Nobbly Nics + sealand and change them over when I hit SA? Based on recommendations the next set of tires I'll use will be 27.5+ Nobbly Nics, but maybe these will overkill for a mosty on pavement 'pre-trip' in Oman? Also as a sidenote, do you really need mid-fat tires for the GDMBR or should I be looking at some 29" 2.2 etc?

Thanks!