Yeah, I'd mulch it... What kind of mower are you using on that slope?
On the edge of that bush where the photo is cropped off... looks a bit steep... wish I could see more ...
Terracing is not easy to get right... It usually creates more problems than solutions, from what I've seen....
Incidentally... did you say that you dug a hole, replaced the clay with compost?
I would not add organic amendments to the planting hole.
The extension service has done experiments with adding organic amendments to planting holes, and found that they keep the roots wet in the winter... and dry them out ahead of everything else in the summer.
Everybody thinks that they need to get that clay out, and replace it with some potting soil or something... but it doesn't work.
I tried it once, too...
