360A is invincible from the third frame.
360B has no invincibility but it's almost twice as fast, and recovers much much faster. Not to mention it does a good chunk more damage. Always use 360B to punish instead of 360A when possible.
A key aspect of Tager is never failing to magnetize an opponent with your combo. You should never end a successful string of attacks without magnetizing them somehow. Without magnetism, you lose. (unless your opponent is really really bad)
Get used to backstepping and punishing with a command throw.
Get used to blocking on wakeup as well. That's right, blocking. Tager still has to know how to block things. You can only really improve this by getting MU experience with all the different pressure strings out there. Tager's 360A is a powerful tool for forcing opponents to make all their pressure strings gapless, which is usually not very difficult to block either. If they put a gap in their pressure, 360 or 720 their ass to oblivion. A lot of people hate Tager for this reason (they call it 360 spamming instead of asking themselves what they're doing wrong)