It depends on the thickness of the plywood you are using, but yes looking at it I see that it's similar in style to the number 2 example I gave.
You need to realize you are putting roughly 800-1000 gallons in an enclosure. i didn't bother to do exact calcs but it's just a guestimate. Anyway, that's 6500-8000+ lbs of just water not including a wet dry. Overbuilding doesn't make the cost go a lot higher. 2x4's are cheap. Wood is generally cheap. With that much water you are going to possibly need to reinforce your floor joists, you'll need a hefty stand that can distribute the weight well. It's not the ovrbuilding of monsters that costs money.. it's the fact that things cost money. Your glass along is going to cost a fortune for the size parameters you have posted. Sealing the tank will not be cheap, however some methods are cheaper than others. Filtration, pipes, elbows, t's, etc all cost money. Pumps large enough to handle the massive water turnover cost money. I think the first thing to discuss rather than how to build it is how much do you have to invest. Then ask a few of the people here who have built tanks how much it cost them in the end... the overbuilding isn't the skyrocketing factor.