Hmm....how to start using lv1 attacks instead of mindless Z bashing? I never use them. How are they even useful?
L1 spam is natural for me since I'm not a good button masher; I charge when it's possible, and shoot while I still can't charge again. Keeps my left hand rested. And since it's automatic for me, I change the way I play to better put a character's L1 to use.
One thing I noticed from your replays is that you aren't actively, er, activating spirits. Keep in mind that while non-activated spirits blown up in a chain will destroy bullets, non-activated spirits blown up individually won't. This is where a decent scope comes into play: you'll want to activate spirits before shooting them. They blow up easier and destroying them becomes infinitely more useful.
Of course, activating spirits with Youmu is tricky because her scope is horrible.