Yeah you may be right that she needs a bit more overall than what she's getting now, but it may be less than what she used to need, of course I can't say for sure, but you know her best, you know how she is etc.
Yes I think you'll be able to review things after a week of trying the later nap, that may mean you decide to evaluate again after a further week, or push further, or try something else. Bear in mind that she may find she's more tired even after her usual nap length, when you push it later, so probably keep BT the same time rather than pushing it later to keep the same A time, iyswim? Also, I hear you on BT resistance with longer naps, personally I found DS needed 2h for some time, it just got later and then eventually shorter too, but again, your DD will be different and you know her best
As for the morning CN... Personally I never found that helpful once DS dropped it, we found EBT worked better for catching up, but I others have found it works. How long has she been on 1 nap solidly now?
As for the EWs and NWs, don't forget to give her time to settle herself before rushing in, you never know she may surprise you. And of course you can probably chalk some of it up to teething and SR, it will pass
Btw we finally had a good WU this morning, poor thing was so tired and had EBT again, woke up twice in the night needing her nose cleared and meds/teething gel, then was still asleep when DS came in at 6.30, let her have another 10mins as I was enjoying listening to her obviously dreaming