I shoot a lot of sporting clays, fun and serious. I do shoot a O/U but I use light mods most of the time, my go to load is a 1 oz 71/2 1150 Clever featherlight, the only time I ever change chokes is if we have a lot of on edge really long targets. This combination will work 99 % of the time. The lighter loads seem to pattern a little tighter.
Have fun enjoy, and good luck. Since you are shooting an auto you may want to use 1200 fps loads, you won't need anything heavier than that, The thing about payload, shot size and speed varies from shooter to shooter. The 6" between our ears sometimes gets in our way.
You cannot believe how many shooters who were max load shooters have converted to shooting the Featherlights after watching the effects of this load, and choke combination.
Buster