Ya, with only a 2" sandbed I would skip the PVC and just use eggcrate. Nothing wrong with a 2" sandbed, I just think PVC would be way overkill.
On my 29G I have rock against the back of the glass because the tank is so narrow, but on my 75G I made sure to leave the back open for flow reasons (learned this lesson from my 29G) as well as more swimming room. I also have a tunnel that goes through the center of my rocks all the way to the back, and when the lights go out my engineer goby turns my tank into a Figure 8 racetrack, he goes zooming all over the bottom of the tank in figure 8 patterns, but does it pretty fast when the other fish go to bed. Pretty cool to watch, never seen him do that in my 29G which he grew up in for about 6 years before getting a bigger home.
On my 29G I have rock against the back of the glass because the tank is so narrow, but on my 75G I made sure to leave the back open for flow reasons (learned this lesson from my 29G) as well as more swimming room. I also have a tunnel that goes through the center of my rocks all the way to the back, and when the lights go out my engineer goby turns my tank into a Figure 8 racetrack, he goes zooming all over the bottom of the tank in figure 8 patterns, but does it pretty fast when the other fish go to bed. Pretty cool to watch, never seen him do that in my 29G which he grew up in for about 6 years before getting a bigger home.