Hi Jodi,
I am still seeking for answers myself and the biggest one I have is teething! My DD is really struggling with it and I have tried several things such as yourself. My DD is also EBF and I have noticed when all the changes started to happen that she was needing more so I really made sure she got more and I feed her more often to get my supply up. That may have been part of the problem, but I would do it all over again to make sure she has enough to eat. With my first daughter it was around this age that she started needing more and I didn't realize it and my supply droped and then issue after issue with BF started, so I think for me BF has caused some of these issues.
I too truly do not understand why my DD does well at naps and so poorly at night. I have been doing well with her naps as you have and she goes to bed at 7-7:30pm. The one thing I was going to suggest was to see if you were doing the dream feed. I started that with DD and it has seemed to help get her a longer stretch at night. Sometimes... It use to be that she would wake up around 5 or 6 and I would feed her and she would go right back out, but now she wants to be awake and stay awake, so I have been fighting that with ptt/shhh and that seems to be working... just slowly. The major issue I have found is overstimulation in the evenings. The calmer evening we have the better she goes to bed, still some fights, but not as bad. Last night it was a 2 hour battle! We had company over and I tried to keep her quite and got her to bed and took my time away from the company, but she could still hear what was going on (even though we have a white noise for her) and it was a battle!, but she slept until 5am so we are working on it! I just wish with Touchy babies it was a little easier.
Anyways... I don't know if my information has been helpful or not, but I thought I would pass on what I have been doing, it hasn't fully worked yet, but it slowly making some progress.
Maybe we can console each other through this!!