So sorry, I forgot to add my experience and setup. I sadly just use my phone, though I'm looking into getting a mic. As for experience, I have been cast in multiple fandubs with an old server called Undead Dubs, and also am currently working in the project Your Turn To Abridge: Fandub By Majority.
I sound a little like a broken record at this point, but I love your acting intuition! You're fantastic at instantly reading the feeling of a line. What I will say is that you can take more time. Isolating your takes of the first line, you build with this constant upward momentum, which is great, but you don't give the line time to breathe. You can have that upward feeling without building it straight up. Think of it like a staircase. You're still moving up, but taking a pause on a word or in between phrases or letting the volume fall a little isn't going to make that staircase suddenly start going down, you're just on the top of a step. I want you to walk up that staircase instead of running. Don't be afraid to take some more time.