i would also spend time with romantic sonatas , you need to get a grasp of larger scale and extended form pieces like rhapsodies as well. Maybe look at doing both of the Brahms Op 79
Guys the OP wants etudes. So I'm going to suggest some etudes as I have played ballade 3 as well as a few of his etudes. I'm assuming you mean Chopin etudes? I'll go through them.op. 101 - No, harder than ballade 3.2 - No, harder than ballade 3.3 - This wouldn't be a bad choice, especially the very beginning. It's got a similar start as ballade 3, using just a few notes to create a beautiful melody. So those notes have to be played very carefully.4 - This would be a real challenge, but finger deftness and independence is required for the dolce section in the middle. Also near the beginning those little trill-run, trill-run, trill-run is hard to get all the notes when you're under pressure of the audience.5 - Great choice I would really recommend this. The last few measures are really really hard though.6 - A good easier choice.7 - I would stay away from this one. It's very hard and you probably wouldn't use the technique that much.8 - This would be an excellent choice. I might suggest this one, though be prepared it is VERY, VERY HARD!!! Much harder than it sounds. But quick, light runs are exactly what you need to practice for this piece.9 - Probably don't need it.10 - A good one for this piece but probably harder than it.11 - Nope12 - It would work but I would suggest another one.op. 251 - This would be a nice one, it's very manageable.2 - Another good choice.3 - Maybe but it's very hard.4 - Maybe but it's very hard.5 - It's a nice etude but I would suggest a different one.6 - It's very very hard, but I didn't find it much harder than ballade 3. But you wouldn't really use thirds anyway so no.7 - Maybe8 - No.9 - Yes, but it's harder than it sounds.10 - It's very very hard, maybe harder than ballade 3, but even if you play it slowly, you use octaves a lot in ballade 3 it could be nice for that.11 - NO! STAY AWAY!!!!12 - Would be very helpful if you could play it.All of the trois nouvelles etudes are GREAT and would prepare you very well for this piece if you could play all of them perfectly. They really are great pieces that don't get enough attention IMO.Just my 2 cents. Hope this helps.