New Guy,
Hold up a bit on deciding on the simple two-oval layout. 4.5 ft x 8.5 ft is a pretty large space, and you can, with very little extra cost, do a layout that is more versatile that the one you have shown. Especially if you are willing to add just two more switches, and really especially if you are willing to use the old school 1950s hand throw switches, with the little upright red handles, positioned fairly close to your control panel. (Throwing those switches by hand is lots of fun.) Those switches only cost about $20 each.
I had to pull my layout of track apart temporarily, to do some painting and begin screwing sections of track down, but I should have it put back together in a couple of days. I can send you a picture of it if you would like. I am sure other members would be willing to show you more complicated (but basic) layouts in a similar space size.
I know that you are trying to keep it basic and simple, but I think you can do that easily and on a more versatile basis, with very little extra cost and effort.
Mannyrock
