Mike,
The obstructed site may well be the better one for several reasons. If its obstructed, particularly to the south and east, this may help with skyglow. I have no problems using a partly obstructed area because I don't waste my time looking at things on the horizon anyway
If the obstructed site is only obstructed to within 30 degrees or thereabouts of the horizon is fine, also if there are gaps in the obstructions for the targets to move through will be fine. If it meets those sort of criteria it sounds good, particularly if it is the closer area to parking and amenities
CS-John B