Thanks ShinobiSlash
I've been working on figuring out a suitable control scheme. Controls can be customized, but the default needs to feel right. I've wanted to keep it limited to two buttons in addition to the direction keys.
In designing the control scheme, I've been thinking about the relationships between fingers and the dexterity and endurance each have. How a person might resort to using one over another in most cases, and designating that finger for either the primary or secondary key.
With various mechanics involved, and having to do more than one thing at once, there is a coordination involved- the mind sends instructions, and if the control scheme isn't good, the signals might cross and fingers press wrong keys, etc.
So I've been working on splitting things appropriately to prevent this from happening.
At the moment, I have the index finger controlling the attacking. The middle finger controlling the grappling, and then the other hand controlling movement/jumping/boosting.
I'll continue to gauge the controls to see if this is a good scheme. I know that controls can be sometimes difficult to teach to new players, so I'm keeping that in mind.