“almost slick centre section but with grip on the outside for a bit of confidence if the track gets a bit loose”
Id have thought if confidence is an issue she’ll not be leaning the tyre/bike over to get that outside tread to really bite?
Something with some low (rather than almost nothing) tread might be better?
Personally I found tyres with near centre-line-ridge-type tread, like maxxis crossmarks although rolled quite well could slip out under breaking/pedalling (okay a fair bit of) and I never really trusted them in the loose or to corner on properly
My Michelin Dry2’s are maybe a touch lower tread but dont have a centre-line and I find (in the dry and not too loose) to be more predictable and trustworthy all round, while being almost as good rolling.
On-one have the folding 2.15″ dry2’s for £10 atm (as big as 2.25″ maxxis (bigger than 2.35″ maxxis), slightly bigger than 2.25″ schwalbe)
The 2.0″ versions are better rollers though, being a bit lighter/smaller, but still big for a 2.0″
They are still an offroad tyre, so not anything like slick quick on the road
” I think a skinnier tyre will have less rolling resistance”
On a (smooth) road/smooth surfaces yes, in the rough I believe not so, a fatter tyre more easily ‘deforms’ to rough surfaces so rolls better, or so Ive read