For scale practice or transposing, no need for the keys with 7 sharps or 7 flats. Chuck out C# major, for instance: and use Db major instead.
There are also the keys with 6 sharps or flats, that are enharmonically equivalent. For the piano keyboard, Gb major is the same as F# major, for instance. Here you should keep both. When you need to transpose to one of these keys, you can use the one that makes it easier.
If your piece is in F major, it's super easy to transpose it up to F# major: all you need to do is change the key signature. The notes on the staff stay the same. If the piece is in G major, and you want to transpose it down a semitone, it's better to use Gb major.
I think it's a good idea to write the actual sharps and flats on the back of each stick.
