Your lawn sounds neat to me. Even the shedding trees. But if you want some variation, maybe you could try some large rocks. I have a black thumb, can kill any plant. Also, I don't really enjoy planting and watering and all the hassle of caring for plants so I put rocks in several places where nothing grew naturally. The rocks look natural and once you get them in they require no work at all. I planted some plants that come back every year in the areas between the rocks around the hot tub and somehow without any effort at all, they've survived.

My back yard is totally wild. I don't even try for the "groomed" look. The trees shade almost the whole 2 acres so it only has to be mowed about once a month (Either I or my husband speed around like maniacs on the garden tractor for a while). The creek is just there. I planted wildflowers in the sunny areas and they come and go on their own.

Not much work really, but I think it's pretty. I love it in the morning for breakfast and on warm summer nights for dinner from the grill.

I think if you enjoy gardening, go for it, but personally, I think I enjoy "un"gardening.