What if ygo had commander? a question asked many times. Here is my idea! Like it, or don't. I can't tell you what to do, I'm not your mom... yet...
60 card singleton
No archetypal cards (legacy support does not make an old card archetypal)
Mono-type or Dual-type, with 5 off-type slots. 10 monsters in your deck must be normal monsters.
No extra deck monsters, except fusions.
All fusion summons can be performed through contact fusion. Poly just lets you fuse from the hand.
Ace monster must be a main deck monster. You may return it to the ace slot when it leaves the field. It cannot return to your ace slot if it left the field for the cost of a card you control, or from the effect of a card you control.