Don't scan more items in an attempt to increase your BRLA. It's more likely to backfire than anything else. The way BRLA is calculated means 1 less error increases it more than 1 extra scan, so you definitely want to find a way to decrease the amount of errors you have. Ideally, you just want to scan the thing you're supposed to. That means matching the image, or DPCI when it's a casepack.
Training is #1, obviously. If everyone knows what to do, there's little reason why you wouldn't have green BRLA. Outside of that, you want all locations properly grouped. Any exceptions to the norm should be labeled (such as openstock shelves). You also want fewer DPCIs per location. Adjusting shelves so that you can fit more WACOs or shelf locations can help with that (having casepacks stacked on top of casepacks stacked on top of casepacks just increases the odds that one will fall behind and get registered as a ghost by a TM who is moving too quickly/lazily, only to then get registered as a baffle by someone else -- that's two errors over one casepack). Having someone do the Backroom System Audit can help as well, as it will direct a TM to fix suspect locations.
In my cereal aisle, I have all my openstock shelves marked with blue tape and a label that states "OPENSTOCK". I limit each openstock location to less than 4 DPCIs, if I can help it, and I adjusted my casepack shelves in a way to prevent someone from stacking casepacks on top of one another. I made sure I had no z-locations by grouping every location in my aisle as well. If I find time (not often), I will Audit shelves at random just to be safe (SFS is the bane of my existence). Only time I drop below 99-100% BRLA is when I help other areas with their pulls. Even then though, you can "cheat" the system by backing out of a pull when you hit a problem location, Auditing it, and going back into the pull. Only works when you have the time to actually do that though, which isn't always the case.
Always want to make sure every casepack has a label too. If the label is missing or it's a mispick, print a new label and slab it on the casepack, along with writing the quantity. It makes pulls a lot easier, especially now that we can't key DPCIs in manually anymore.