I started my FTG life with SFII so I guess I go for Capcom 6-button style. In MUGEN sense 3-button, 4-button, and even 5-button are welcomed. Again in MUGEN anyone can change whatever button layout they wish to have.
Technique wiseI love normal move chain combos, guard counter, and "dare-to-touch-me?" counter, power-up,.........in no particular order.
Game play wise, Samurai Showdown systems, SFIII/IV systems, Mortal Kombat systems are very joyful but mugenizing these systems is tough!
My least favorite game play: MVSC1/2/3 air juggle style