First and foremost, congrats on getting the OM position!
Working in ART, I would recommend the looking out for the following to improve CPH:
1. If the container is pallet loaded, make sure Unloader A and Unloader B are effectively transitioning from pallet to pallet without any down time. Once the unloaders get half way done with the current pallet, one unloader ought to continue throwing while the other one is prepping the next pallet by cutting the shrink wrap and moving out empty pallets/trash. When the line is backed up, one of the unloader should flex out and assist the line processors to get the line cleared ASAP, whether it be assisting building pallets, changing out cage carts, receiving pallets, stack and push, XSing, etc. Unloaders play the biggest factor in maintaining a high CPH especially with a high flow trailer.
2. Streamline the XSing process -- the person that should be the main person XSing should be the fastest one on the line. He or she should be able to run at least 10CPH by themselves receiving, labeling, and putting cartons in the cage cart -- once they clear the line of XSes, they should quickly flex to building pallets. My observation is often times the slowest/laziest people will jump on to do XS and take 5-10 minutes to XS 10-15 cartons so they don't have to work hard. If the line is completely backed up with onsies and twosies, I recommend having the entire line processors jump on -- 1 person should organize the line by DPCIs, 1 person ought to be receiving, and 1 person ought to be applying labels and throwing them into the cage cart.
3. Have your trainers train TMs to quickly recognize when a trailer has to be moved to the NCN dock. Everyone on the line should be trained to know how to end appointment, switch appointment, and move trailers to the NCN dock after they notify the LWW/OM to avoid downtime changing to adjacent trailer. That means the line leader should be checking the contents of the container using the jump code RAQ before starting a trailer and they should routinely check in on the unloaders.
4. Switch out your TMs routinely from ART, manual dock, and modified manual dock to prevent burnout and quiet quitting. Bad behaviors/foul attitude will infect a line or the set and it will be very hard to turn that culture around.
5. Just remember your CPH isn't end all be all -- there are other things to think about such as turnover time, gaps, etc. Some trailers will be a nightmare to work, but I believe on the system it shows you the expected time it would take to finish a trailer. Not really accurate, but you know if you have a low density truck your line will probably have a rough night, or a trailer with big cartons (sterlite, fruit of the loom, sleeping mat/bags) will just naturally result in low CPH.
It has been awhile since I worked Inbound, but those are the things I would always look out for.