Looks like a normal installation, but you will most likely need to raise the units in the near future. Might as well have it done after your landscaping is put in. The units behind our previous home had to be raised because after 10 years, we had accumulated about 12" of mulch around them. Also, the units started sloping toward the house.

Looks like the installer took the path of least resistance which is par for the course on most new home construction nowadays. The rest of the house had/has various issues I'm working through. I've looked at all the other units in the neighborhood and they are all sitting up higher.

I'd like to get these up another 4 inches which would allow for grading and finishing the areas off nicely.

From the last photo, my take is that drainage and the path of downhill runoff relative to the house and its positioning on the land should be of greater concern than the height of the pads the compressors are on. You can't allow that erosion to continue. Address the drainage and both the compressors and the pads they're on will be less of an issue.

Also, in the second photo, the large downspout to the right of and uphill from the compressors probably needs to be connected to a drain line to funnel the water away.

I agree that the negatives of the compressor site chosen seems apparent but there also seem to be other issues to deal with too. Good luck.

Absolutely and addressing the drainage is on the list. I've already spoken to our irrigation guy and since he'll be out with the trencher we'll address adding drainage at that time.

Why haven't you already recruited some one to help you raise them? There's plenty of flexibility in lines to allow raising them. It requires less time than we've talked about it to raise pads with pry bars then shove another pad,concrete blocks,dirt,sand or graval under there and let it down.