I'd keep the bike simple. 1x chainring up front is all she'll ever need with a long cage derailleur on the rear and an 11-36 cassette if she likes climbing. I'd also avoid Kojak and other skinny tyres - in the real world of imperfect roads these slow the bike down and make the ride feel harsh with the 20" wheels (I've tried these). The only good thing to be said for them is that she'd save a little weight. Right now I'm running Swalbe Marathons (not particularly light at all) which I keep pumped up to around 90psi. These have good puncture protection and roll over a lot of kilometers without complaint. I'd also consider keeping flat bars instead of drops as the bike is simpler and easy to transport without hooking onto things if folding it frequently for storage or transportation is important to her. I also find flat bar shifters much cheaper than brifters, etc.
Anyway, good luck whatever you do!
Last edited by joey buzzard; 01-31-21 at 10:22 PM.