some ideas:

So you know, the picture does not include enough space to the left of the house in order to know if you have room for a small tree over there.

Consider that the whole stoop is part of the entrance. The skinny walk up to it seriously degrades the intent of the architecture. In order to have it be acceptable, you'd need to widen the walk at least to the width of the center opening. It could be as wide as the entire stoop, but that's probably not realistic as it would cost considerably more.

Planting tall things in front of the stoop does not help to emphasize that the stoop is an entrance path. There must be other places in the yard for such things if they are desired.