Hi DLally,
Every system peaks at some point, the question is "do we need to anticipate and plan for that peak?" The recommendations made by vC Ops guide you to systems that may have reclaimable resources due to over allocated VMs. One thing to keep in mind is that the "reclaimable waste" is an opportunity, not a target. In other words, vC Ops is offering recommendations to avoid or delay hardware upgrades and also telling you what you can do with the resources you have today based on utilization. A lot of times admins see the "Efficiency" score and treat it like an operational problem and that's not how you should look at it. Generally speaking, don't worry about chasing down over sized VMs unless you need the capacity to add machines or avoid hitting the "time remaining" wall for a resource. Using "All Metrics" to validate peaks in resource areas over a 7 or 30 day period is a good idea when considering resizing.
You can fine tune vC Ops to take peak behavior into consideration using policies. You can adjusts the Oversized and Undersized determination as well as include Stress (a better word for 'peak') in time remaining and capacity available calculations. Also, there are some OOTB policy templates that are tuned for 15-min and 30-min peak workloads. Check those out as well.