Jack--
I have an uncle in Florida who's been collecting Cubans (real ones, not Florida ones) forever, and he keeps them in a number of old desktops that are 100% cedar (I assume Spanish, but don't know for sure) on the inside. Every time I light up one of his old stogies, I get inundated with the taste of cedar that IMO really interferes with the cigar's natural flavors. I've heard from a few other folks who've had similar experiences, so I'm just a little weary, as I like the smell, but not the taste of cedar.
(An extreme, non ISOM example--the Don Melo Centennario line makes pretty good sticks, but they pack them in these cedar trays--I tried one of the Liga T's I'd had for abt 2 years, and ALL I tasted was cedar. I've since removed the trays).
I should stress that my uncle's 'dors are all desktops; the cedar is solid (no slats) and there's very little room for any kind of circulation in them. I have a large end-table style humidor with roughly the same proportions of wood and glass as you, and I've never had a problem. Plus, virtually all my Habanos are stored in their boxes, if that makes a difference, which is contested, but I think it does.
Talk to you soon, Brit