A couple of pictures taken from further back (but not too far) will help.

You got it!

All of those cut ends need returns added to them! Can the installer comeback and finish them out properly?

Here's a video that will explain 3 common ways to finish the ends. A return, the second method in the video is what we've always done.

https://www.youtube.com/watch?v=3QtxwcD7yP8

They were not done in the usual way. The base along the treads is part of the issue. There should have been wall stringers placed before the steps were installed. That would eliminate much of that awkward appearance. If the rest of it feels too boxy, you might add some decorative profile to the top of the base for a more traditional look.

It’s not impossible to retrofit better trim. But it can be tricky. Browse Houzz and Pinterest for stair trim options for ideas. Here are some. https://pin.it/4fvZhVb
Oh, and if the gap between wall and tread isn’t too bad, you could just add shoe on the tops of the treads like last photo.

What exactly do you not like besides the flooring corner mistake?

I would do exactly like @PPF.has marked to a tee. The only additional thing may be if the tile is for a fireplace, I would make the edge of the hearth extension look like it has some depth, like 4" or so.