Hey coool, I'm playin both of those right now.
2nd movement- this piece is the easiest technically, there are barely any pedal markings, which adds a bit of difficulty
Brahms- The leaps and the huge span that the left hand must cover in the single notes is what causes this piece to be difficult.
1st movement- I found this about the same as the Brahms, but it is more difficult in certain sections.
3rd movement- There are a ton of contrasting sections, fast slow, and some very awkward finger positions. This is much more difficult than the 1st, 2nd mvoements, and also the Brahms.
I don't know what you mean by pianostreet rating.... so I'm just gonna say what I think

2nd movement, Brahms, 1st movement, 3rd movement [increasing difficulty]