I’ve used that guide 3 times now over the last 3 years. The descriptions are superb!
The Soller ride up to Balitz and Fornalutz is great although quite short.
The Esporlas ride is a great day – some excellent “secret” singletrack and a great descent after the scenic shore-line section.
The Arta ride is away-from-it-all but only has one good bit, but that’s actually a really good descent down to a lovely inaccessible beach.
All the stuff around Lluc is well worthwhile, and there’s loads of other options in that area as well. You can ride up from Pollenca via Binifaldo off road, do one of the loops from the guide and return the same way. All good. The offroad route between Lluc Repsol Garage and Cairmari is a favourite of ours!
The ride near Palma (Na Burguesa) was also good, and I bet there’s a lot more in that area to explore as well.
Nothing’s mega technical in those rides, though, but they’re all good days out and you’ll hardly see anyone off road.
Take the MTB. There’s too many road bikes on Mallorca already 😉