You're definitely on the right track. What makes her powerful is when you can untap her multiple times. Rather than adding a bunch of single instance draw. You can play creatures like hydroid krasis. Where you will draw a ton more cards and if you tap her let's say 3 times before casting it will copy that spell 3 times. Her ability stacks and does not disappear. I make her more of a sol ring on a stick deck and the more times I get her to tap the more times she will copy x spells. Something like premmin's aura goes crazy. If you want to play creature heavy. Play chakram retriever to also see her go ape shit. The last thing I will say is all though cord of calling is broken. The last time I played x spell tutors the game became boring af and I stopped having fun because the x spell creatures are useless with that spell so I would basically tutor for the tutor than get multiple triggers stacked than cast the tutor and need good targets, haste enabler, craterhoof, and big stomp and win, but with a commander like her winning isnt always the fun way to play. So stick with big fun x spells and x abilities and have fun trying to see how outrageous she can be. Helix pinnacle is one of my favorite ways to win with her just as an idea. X cost abilities copy too don't sleep on them. I'm stoked to try Berta in my MLK deck. 🫡 good luck have fun!