Perhaps you might like the work of Mompou. He died not so long ago - the 1980s I think.
Also Maurice Ohana.
Or Dutilleux.
Or Gnattali.
There are quite a few pieces by Gabriel Erkoreka, published by Oxford University Press. The least demanding are the earlier Nubes.
There are a couple (at least) of short pieces by Murail, Mandragore being one, and some hommage to Messiaen being the other.
There are some very recent miniatures of Boulez as well. Also the Wasser-/Erden-/Feuer- klavier set by Berio. Also dead, by the way.
Some early pieces by Xenakis have come to light and have been recently published.
The sonatas of John White, of which there are 169, present you with quite a choice (enquire at
www.soundandmusic.org I think).
Also Dave Smith (at the same address) has written a lot of piano music.
The Gershwin Arrangements of Michael Finnissy might also appeal. Many of these are not as challenging as some of his other works.
Morgan Hayes (publ. Stainer and Bell) has written quite a bit of piano music: the two sets of Strides might be good places to start.
There is a lovely Ballade by Kaija Saariaho (published by Chester).
Bent Sorensen is a good composer, but I don't know if he has written piano music.
Perhaps try Valentyn Silvestrov - very intimate, evocative music. Everything from sonatas to miniatures. Published by Beliaeff. A current favourite of mine.