So
@jmmzpsu14 I really don't understand the support question vs the drawing.
The drawing looks like you want to mount it in a shelf fashion, sorry.
Then, as long as the slab is supported or secured I mean, it shouldn't warp, but thicker would take longer to crack.
If you can, place the growth rings in a rainbow arc not cupping up, but narrow at the top, and wider apart on the bottom
side. That will HELP, prevent cupping which will hold water, but, you can place a board in the Sun
and it will draw the ends and or edges up. Secured down, will prevent most of that.
Maybe
@Vinnie Charity can dial in your illustration better than I.
View attachment 366423View attachment 366424
But here are 2 examples of how I've supported live edge slabs in a shel like manner.
You can scroll through a listing to find dimensions
www.ebay.com
www.ebay.com
Live edge may or may not include bark, still legit without. With, may separate outdoors IDK.
Cracks and crevices should be filled too being in PA (freeze/expand) if outdoors for the Winter.
I've never used a resin filler, and an epoxy pour plastic type finish, like a bar top, will scratch terribly.