"Apparently charging and performing other actions are viable" 

I'm not going to say anything on the rest, but yes, charging and performing other actions are viable as long as the two do not clash. You could not charge your burning sword while hitting people with it, for example, but you could charge your burning sword (if it does so on it's own) while kicking. The knowledge of such was brought upon me the hard way by Rilla.

Everything else, gold.