hi!
His daytime sleep may need to be cut down.
There are a few ways to do this which you can find here:
The 1-0 transition...Advice and Tips to help you through.I DON't think he's necessarily dropping his nap, but the tips on here help with the process before dropping really starts.
The chatting, delaying bed time in any other way, and needing us to fall asleep were all signs for reducing daytime sleep (in a way to make A time to bed longer) so that he would be tired enough for bed. You have a great routine so I would start by capping the nap at 1.5 most. Try that for a few days and cut back another 15 mins for another few days. Do you find that he goes to bed more easily on 1 hr nap days? If so,perhaps start there at 1hr nap max, and bedtime the same.
Wrt the bed transition, a lot of reassurance, a night light, a lovey for comfort, and consistency helped our son with staying in bed. I bet he's also processing all the changes and combined with the developmental leap around2yo, it might be keeping him up when he wakes. We can address this more if the shorter naps don't help him sleep through. But I would probably address this before new baby comes as it will be harder to have the energy to do so afterwards right?! Hope that helps!