I do practice Hanon about 1 hour per day, purely because ( gasp! ) I like it. But it is not necessary. However, I do think that some equivalent is a good thing.
So, If you're into practicing, I think that czerny does have some beautiful etudes you could try. The easier op. 299 ''School of velocity'' (example here:
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op. 740 ''The art of finger dexterity'' ( example here:
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these are the books that could be apropriate to your level of play. Contrary to many peoples opinion, I think they are very beautiful in their simplicity and they certainly shouldn't be played as dry technique exercises, as people tend to take them. They are nothing easy aswel, if you strive for perfection.
In addition, they are a great stepping stone for Chopin or Moskovsky etudes.
Ofcourse, you should never overdo Hanon or etudes to a point when you wanna bang your head against the wall. Always in healthy amounts. And pick some ''real'' pieces aswel for sure. Harder pieces are always a great motivation.
If you practice 20 minutes per day, I personally wouldnt bother with Hanon and pick something more enjoyable instead. If 20 minutes are enough, that is relative and depends on what you want to achieve or how fast you want to progress. But if you are so much into the piano, I am sure you can do a little more =)) It just needs the right piece to work on, that will drag you.
In order for someone to recomend you an apropriate piece of music, you need to write what is the last things you play/played so that one can guess what level you are at.