Staffing Models in ALF---What Works For Your Facility?

I'm the DNS for a 42-bed assisted living facility in Oregon. The administrator and I are considering changing our staffing model from what's basically NO model to a more formal arrangement, e.g. assigning a set of rooms or a floor to each caregiver.

Currently we have 2.5 staff---that's one med aide, one full-shift caregiver, and one short-shift shower aide/caregiver---for day and evening shifts (something I'm working hard to change, as it's NOT enough), and 2 (one med aide and one caregiver) on noc shift. All staff answer the call lights, serve out the meals, help out in the kitchen after meals, and help the residents who need it to get back and forth to meals, activities etc. The short shifter does all the showers/whirlpool baths plus assists with meals and caregiving.

I think it works well and prevents that "Oh, that's not my resident" mentality that seems to occur when staff assignments are divided up. But we, like almost everyone else these days, are trying to do more with less---well, not exactly less, but without adding extra staff. And the staff are getting burned out........several long-time caregivers and med aides are talking about leaving.

Any input would be appreciated. Thanks!