To me, ground is always better if you have the option.
Another thing is to plant herbs in WELL DRAINED raised bed. Have a different bed (or area of bed ) for the perennials and the annuals.Mostly because the two group need different care. leave open space between them. Consider how big they can get down the road. Even within the perennials they need different care, like onion family cannot be treated like Mediterranean herbs. So growing herbs require some time to know them. Growing herbs as ornamental is one thing and growing them for daily culinary use is another.

JMO

Ground is always better than pots unless your soil will be a huge problem in regards to the soil type needed by the plant. But many plants can often deal with a wide range of conditions that are outside their optimal preferences. Try the ground first.

And as someone who grows both medicinal and culinary, never intermix the two types of plants unless you are talking about medicinals that are safe to eat - example: things like calendula, borage, lemon balm, mint, etc. Keep any medicinals, especially the toxic ones out of the spaces for edibles. Locate them in separate gardens.

FataMorgana

The thyme should be just fine with freezing at least in the ground it is. Maybe lots of freeze/thaw cycles have damaged some of the roots.

The only thing you might want in pots is mint.