Hi Jbjack,
I only used Metal bracing on my 150 gallon build. I would not use it again because it limits the surface area you have to nail the outside skin into. I found that using pocket screws (used on 144g) was far easier and cleaner to do. Your framing is perfect, don't second guess it.
The 150 was skinned with Maple. I couldn't find nice grained sheets at depot or lowes and ended up getting it at a true lumber yard...inspect your wood carefully to make sure you get the grain pattern your looking for.
I can't remember the exact color I used, but it was miniwax brand stain. Make sure to get some wood conditioner and follow the directions to get the effects your looking for. Most stores have wood samples with different stain treatments on them so you'll have an idea of the finished look. Be patient, sand between coatings, it's worth the extra effort. And seal it with 2 - 3 coats of poly.
Hope this helps.
MADURO - very nice stands, i hope my fishished stand looks as good as yours. I noticed you used metal bracing, i didnt, do to my wood braces are placed on wood, is that ok? hope so. also what kid of wood did you use on the one you stained brown, turned out very grainy, I love that! also what kind of stain did you ise?