And finally, I had posted this suggestion before, but deleted it when it appeared it had been passed-over.
What?!
Near any idea is worth leaving alone. Who knows who else you may inspire with it.
I still read very old threads regularly. And have deleted very few. Even downright embarrassing ones remain, just because it did happen.
If requested, I'd think about it, out of courtesy to the OP, but in those (my) "dumb" cases, deletion is almost like a lie. I'm "funny" like that about "the printed word". It's not just mine, or yours, its "ours"
Carey, You could always do a "dry run", without full assembly, and a little squinting,, just to see what it might, actually look like. (I think colored glass would look best there)
I think its a very unique idea worth a one eyed squint, at least
The elevation piers would really tie it together more prototypically, for a less "separated" look. And well designed, the piers will have a truer Art Deco feel vs Art Nouveau with the vase(s), as well as being less prominent, letting the table, trains and other scenery capture the eye.
An open center will also let light through, a "second table" will not.
Platforms for a few elevated buildings or whatever, creating a semi-open center, would be a nice compromise between the two, too.
For a more solid elevated unit, I suggest putting joint seams of the wood, mid track, -vs- right at track joints. It will be stronger that way.