I'm a newish PA too so I know how it goes. 🙂 Our scores are pretty good on the whole, except we struggle to keep our availability score green. One thing our STL has challenged us (well, the whole store as well) is to greet EVERY guest that we see. It doesn't have to be CIHYFS all the time; just a hello, how are you, or even just eye contact and a smile if they're busy. Just to let the guests know that we exist and aren't too busy to give them attention (even if we're pushing a huge cart of produce or booking it somewhere for an important job), can really help. Just initiating contact is great because it opens the door for them to feel comfortable to ask for help or for you to offer some (sales!).
Freshness is big too. I think PFresh sets itself apart from other grocery stores because we strive to have clean, neat and fresh product always on the floor. I just visited a new grocery store that opened down the street and they're huge and cheap, but its DEF quantity before qualify and I know I, and others I know, would feel much more confident purchasing from a place that I know is always clean and fresh, like our PFresh. People are willing to pay for a quality product if you offer it.
Anyway, good luck! I'm liking all the advice as well; always good to learn new tricks. 🙂