Always use your hands/fingers unless the part calls for mallets or sticks. The exception would be if you want the sound that you get from the mallets or sticks ... then of course use what you want, regardless of what the music states.

Some people do use mallets/sticks when the parts are too complex for them to use their hands. Keep in mind that when you use an apparatus other than your hands, you lose the numerous tone variations you can get with your hands. There are a few sounds that you can get with mallet/sticks, but nothing even close to what you get with the hands.

Ah ... well that IS a different story. Yes, if you are the only percussionist and you are covering multiple parts, you have to do what you have to do. I have to make similar decisions when playing in pit orchestras for musicals, plays, operas, etc.

Figure out what you can and can't do, making compromises only as musically or physically necessary.

I love covering multiple parts ... that's what got me into playing drumset and percussion at the same time. Hope you end up enjoying it as much as I do!

I have some bongos. I think they are fun but my band only has two songs so far that require them. So I spend most of my time on my drumset.