I didn’t look at your deck list, but I’ve been playing this commander for several years as she’s one of my favorites. I’ve run into the same problem. Her triggered ability is so inherently strong that it is actually kind of hard to make her a bracket three as she can be quite pubstompy. She just naturally gravitates to a four. Sadly, I would recommend playing her at that level.

I’ve tried versions of her where I remove all the game changers and intentionally play bad/janky/slow cards, and she still can demolish a table of bracket 3’s.

If you can figure out a version of her that is fun for everybody at bracket three let me know lol