I had asiatics in 2 of the containers.They poop out after a couple of years.
My thinking for you is to separately pot the some of the asiaticsand LA's you want to and Put asiatics in containers with coleus.
If I had 8 year buildup of bulbs in a container I would do that.
I often pot a lily and move it around the garden to find a spot for it permanently.
I have used coleus for years,I also used to take cuttings for over winter in the house.I'm just not up to the fuss anymore.
We are in the same zone.so I think your lilies in large containers should over winter OK.I would keep the small potted ones in the garage or someplace where they cant retain moisture,that will rot bulbs.
I have not put any lily other than asiatics in planters just because I never had a proper place for them..
I agree about the orientals,mine are just as happy in the garden.