I’m using a controller while I wait for a 360 PCB.
I put it on a flat surface and use my thumb and index on the Analog stick and I use my thumb, index and middle finger on the Button side. I put both assists on the Left Trigger and Left Bumper so I don’t have to change my grip mid-combo.
You’re pretty much forced to use two fingers on the analog stick because it’s really hard to double-tap forward dash and be ready to block since the analog stick has a lot of throw to it. As for the buttons, I’ve seen people that switch grips in order to do certain combos, like Storm’s Lightning Attack air combos. Ever since I learned fighters however, I’ve been one to rest my fingers on the buttons so a uniform claw position is my preference.
Basically I just play it like a tiny, incredibly uncomfortable, completely unnatural arcade stick. Honestly, not counting a couple of really good players, I don’t even feel shady chalking up 90% of my losses to the fact that I’m trying to play Marvel with an Xbox controller. There’s things crucial to the game that are just impossible or completely unintuitive on a control pad, like mashing out of things, LK+HP commands, PP Dashing, etc.
The analog stick is actually surprisingly responsive, but the DPad is complete garbage. I seriously double tap forward and get a super-jump or a fireball. Arcade stick is preferable if you can afford it, otherwise pad will do if you don’t mind unlearning a lot of things down the line.