Hi there!
I remember the 9mo sleep regression well. Our naps were ok but nights were awful. It is a time of lots of developmental stuff which can throw sleep right off.
Looking at your LO's routine though, I wonder whether it's worth trying to push the first nap a bit later. Usually at this age first A time is at least 3hrs. I think I'd try gradually pushingbthat first nap closer to 3hrs after waking, by 15mins every 2-3days until you get a longer first nap. Then try 2nd nap around 3hrs after waking from first nap?