The dragons to mitosis ratio isnt based off which do I want first, more so you can use mitosis on the daughter copies. Looked at USEM, and the deck is solidly based on speed and EM, which my deck is just built for win rate and some good speed, not ultimate speed. Thats why its set up to be able to work without a rustler. In the commentary for USEM; "What would you do if you didn't have a rustler in starting hand? Cry?" Of course I would suggest putting more light pillars in, like 3 more in exchange for pendalums, but it was so those who start off with life dont have to waste TOO much electrum therefore can just vs ai4 without having to even do ai3 (so by collecting cash from quests do up to ai3 quest) When you have 500 score I recommend doing 1 ai3 match and just click through quests, giving you a good net worth of electrum so you can upgrade any 1 card of your choosing after very little games after 500 score, and if you sell the upgraded cards you win from ai4, you can upgrade more cards of your choosing.
Also Id get rid of 2 heals replacing them for 1 dragon.