If those dimensions are right, it's a 250 gallon tank! And, reaching all of the substrate is going to be very difficult with that height and depth. But, it should look spectacular and you will have room for almost any fish you want to try.
Because of the tank size I don't think it is a good idea to expect to remove the light fixture/hood/canopy to do tank maintenance. So, I would go with an open top tank, with a hanging light fixture or fixtures. The 36 inch front to back depth almost forces you to build your own light fixture, so you can spread out the light over the whole tank. You could use 4-60 inch T5HO lights, with the bulbs about 6 inches above the top of the tank, and get low light intensity, but you would need those lights separated by about 10 inches between bulbs. Then to do maintenance you just raise the fixture another foot, to get more room.
Also, be sure to use permanent plumbing to handle water changing and replenishing. If you have to drag hoses around every time you work on the tank that will soon dim your enthusiasm for the tank.
I hope you start a journal in the Tank Journals forum to let us watch as this is built up - it will be extremely interesting.