Any Prokofiev you could recommend just because he's been a figure if interest for me since I considered music seriously.
Hi cameron,
not really.. .

hmm, but since wolves were mentioned above, and connecting them to Mr. Prokofiev, I remember I only bought somewhen a simple, but funny piano-version of "Peter und der Wolf", arr. by John W. Schaum. That would be far too easy for your purpose, but at least it contains a test / little exam-form, in which young piano pupils are supposed to select the correct theme and assign it to the correct protagonist.
But there's a piano reduction by Prokofiev, too, out there, of 1998 ( Schirmer), and there should be other piano solo versions, too (?) , all of them probably being harder than my Schaum-book (?) - but I don't know how difficult exactly the piano reduction or other piano solo versions are. Can only estimate that they'll be harder than the Schaum arr.
Nevertheless, a
demanding piano reduction / piano solo version of it may be worth a look, I think!

But I haven't thoroughly checked the catalogues either, because there's an overwhelming amount of Peter+Wolf-stuff out there.. . And generally most Prokofiev-works seem to be copyright restricted.
Other works by Prokofiev I unfortunately don't have, and I think you are more interested in his sonatas and piano concertos, so perhaps others may be of help here?
Many greetings, 8_oct!