Hello,
My DD is also low sleep needs.
We went through a developmental regression for a couple of weeks just after her 2nd birthday, where she took longer to settle at BT and woke once or twice during the night, but other than that, for the last two months or so, her routine is usually an 11h15-11hr45 night and a 20-30 min nap, depending on how tired she seems. We have to wake her from her naps. But if we let her nap, say, 15-30 mins longer then it can take her much longer to nod off at BT so she gets less sleep overall in 24hrs. Luckily, L is quite happy when woken from her naps but I know some LOs can be grumpy for the rest of the day if you wake them. What is your LO like if you wake her?
It sounds like you are prob going through the 2yr development sleep 'blip'/regression at the moment so my advice would be to hang in there for a week or so, trying to judge when she is ready for BT as best you can, but when she is settling better, try capping her nap and see if that helps.
You say you had some success with a shorter nap for a few days, then possibly the regression hit.
Some nights even now L can chat and sing for quite a while before she nods off. I thinks it's just her way of processing the day and so as long as she is happy, I don't mind at all.
HTH x