I have no hydrangeas yet in part because I'm not sure if I have a good spot anywhere.

The largest planting area is my front yard which is completely open to the elements and faces E/SE. The back yard is very narrow , faces W/NW and the potential planting area would be several feet below a line of mature shrubs at the top of a slope. I'd have to put in retaining timbers and backfill with soil on lower part of the slope to plant. Otherwise the area is mostly compacted gravel with an overlay of dirt.

Are there types of hydrangea that would do well in either of these situations?