Very much a personal thing I guess and I struggle with all of them. Working from memory and barely scratching the surface:
Bleeding difficult: Rach 3, Schytte, Busoni, Nikish, Zelenski, Abbiate, Ogdon (if you consider it romantic), Henselt, Klindworth, Andriessen, Zichy (keft hand).
Nastily difficult: Rozycki, Moszkowski 2, Linko 2, Dreyschock Concertstuck, Hopekirk, Urspruch, Concertstuck, Willan, Boise, Brassin 3, Bainton, Natanael Berg, Bronsart, Conrath, Labor, Liljefors, Melcer 1, Pabst, Paur, Reuss, Rolon.
Not so nasty: Bobinski 2, Borowski, Bennett 4, Castro, Gernsheim, Hurlstone, Malling, Rosenhain, Rufinatscha, Smulders, Sowinski,
Easier: Bache, Barnet, Broustet, Burgmuller, Cusins, De boeck, Dobrzynski, Dupont, Hartnock, von Holten, Jewson, Kufferath, Lessel, Norman, Parish Alvars, Scholz, Spindler, Street.
Easier short Works: Blahetka Concertstuck, Farrenc Gallenberg Variations.
Concertingly.
Thal