Lateral-The stand will be going on carpet, but it is a very thin carpet. The main reason for the bottom skin is that this tank is going in a second floor apartment and equal weight distribution is cucial. Having the tank rest on just the bottom frame only gives me very little surface area.
Tabasco-I'm in a toss up about side doors, but I hunk I'm leaning more and more toward them. The side opening between the frame is only 12" so they will be narrow doors, but having 12" is better than not being able to get in the sides at all.
Jhs- I know what you mean about hiding the trim and sandbed. I might make the siding come up enough to hide the trim. The only problem is getting the tank up and over the edge. My old 180 had a 3" tall rail on 3 sides to hide the trim and it was nearly impossible to move the tank onto or off of the stand.