elevated benchwork
Another thought. Using the platform and raised benchwork will make ducking under to get into the access aisle easier.
My current layout under construction will be supported by freestanding metal shelving (gorilla rack) set at 48". The framing will be a box or butt joint construction of 1x4's. On top of that will be 1/4" lauan ply and the roadbed will be a homasote-like material, so rail height will be at about 52", and I'm 72" high, so watching the trains at eye level is just a slight dip down, with access to the scenery, trackwork, etc. comfortable for arm's reach. I'll probably do some work from a short stool (and old porter's step would be cool...hmmm....) but hopefully not much.
One section will be built on a 3' high section so that the ground can fall away from the tracks (on a fill and over a bridge, crossing a road and a creek). This way the rest of the layout can be built with the base right on the frame for strength, as opposed to building the whole thing cookie-cutter and riser style. Only the depressed section needs that treatment, a savings on lumber, effort, and time.
Also, remember John Allen dug out much of his basement to build the Gorre & Daphetid, and actually built some of it on areas he couldn't (or didn't) excavate.
Yet another thought...there was a layout in a Christmas house/antiques place near my home town in FL. I remember there was an I-beam vertical support along one long wall of the layout area. There were at least three tracks passing in front of the beam, and one actually went through it. The builder had a hole burned/cut through the web of the beam. Kindof a cool effect to watch trains go through, because even though much of the beam was hidden with a rocky outcropping and the tracks going around clinging to a cliffside, one track went into a tunnel and emerged the other side. You knew there had to be a hole in the beam, but it still played with your mind to see a train going through.
Point is, take the obstacle as a challenge to be overcome. What emerges in the planning process may be a really cool serendipity! Just make whatever is in front of the utilities removable.
Galen