Thanks for the clarification McNinja. Although, not being able to L-cancel every move is lame-sauce.
@MonkUnit: YO, I can tilt the control stick so Samus walks and when I push b she doesn't shoot a homing. Also if I'm in the air and I tilt the control stick and press b, 80% of the time she'll do a charge shot. So, instead, the control stick has to be pushed all the way (smashed) for a certain amount of time and then b can be pushed for a homing. Least, that's what I've discovered. So saying "tilt for homing" seems like a false statement. I'm trying to figure out what's that time frame that I need to hold the control stick for when I push b, I'm guaranteed for a homing missile to come out.
Also, for the missile spam, is there a way to alternate between homing and super without moving when doing the homing? With super's it's easy to stay in one spot because shooting a super is a quick action. But since I have to hold the control stick in a direction for a certain amount of time, she moves.