Why don’t you look at commercially available ones and then just build one you like the look of. I don’t think there can be no right or wrong way as trial and error is what makes it a fun hobby.
Have you thought how you’d join the stainless plates together? It’s a hard metal to work with but you could use thin RSA and rivet the plates to it, it would be quite heavy but with the wind yesterday would be good.
You could then clad the outside like you said with T&G for a smokehouse look.