Reddit mentions of Encyclopedia of Scales, Modes and Melodic Patterns

Well, if you're just talking about just majors and minors up and down a few octaves in a very normal way, at some point you're not going to get a ton out of them.

But you can milk them or a ton more. Have you done arpeggios in inversions? Have you tried playing different inversions in each hand? That last one also sounds awesome as a lick a lot of times. Contrary motion arpeggios?

Same with scales. Contrary motion? 3rds/10ths/6ths? Double 3rds/6ths?

Here's a rhythmic variation I like. It's surprising difficult and will show you just how much you're only comfortable with your scales because of the stopping points at the octave. (from this book)

There are also all sorts of sequence exercises you could do. These are just a few out of a huge number in this book and you could come up with plenty on your own, particularly skipping notes and making your own Hanon-esque variations.

Then there are also variation cadence patterns or just chord shapes (triads, 7ths, or even voicing concepts) in inversions, played through various rhythmic and broken chord patterns (like Alberti bass for example, but the sky is the limit).

And of course you can make sure you're doing other work that has you focus on relatively diatonic chords in context. You can work on chords that are not as common (dim, m7b5) and those that never show up diatonically (dim7, aug, aug7). There's also arpeggio work to be done for these.

You could work on modal scales and apply all the variations mentioned above to discover new finger quandaries you didn't know exists (though sequences are much more brutal in this respect). You could work on other scales. Pentatonics are pretty useful.

You can also apply dynamics and articulation work to pretty much all of these.

While I'll agree at some point you're going to deal with more of this stuff in literature, and that eventually you'll be "done" with a book like this, you're only limiting yourself if you're not seeking out more variations that can really challenge you.

And before you scoff at jazz exercises, technique is pretty universal. It doesn't matter what book it comes from. If there's something you find difficult, it means there's a limit to your technique in that area. Fixing that gap can only help you, never hurt you.

I use this book with my students. It covers all the scales you will ever need to know.

I've been trying to keep a list of the good jazz discussions that come through r/piano. I would start by reading through: This, this, and this.

If it's an option for you, then I strongly suggest getting a teacher. Most of my students come from a classical background and it's quite a shift to get them playing jazz. If you want to learn by yourself, then the thing to do is transcribe. Find a player you like and figure out what they are doing and when they are doing it.

Regardless of if you get a teacher or not, you NEED to listen to as much jazz as possible. I like to point people to JazzRadio.com for starters. You also NEED to start training your ears with daily practice.

In answer to your question on modes, start simple with a C major scale. What you're going to do is use only the notes that make up the C major scale but start on different scale degrees.

• Ionian: C D E F G A B C (simple major scale)
  
• Dorian: D E F G A B C D (you can think of it as b3 and b7 with regards to a major scale)
  
• Phrygian: E F G A B C D E (b2, b3, b6, b7 with regards to a major scale)
  
• Lydian: F G A B C D E F (#4 with regards to a major scale)
  
• Mixolydian: G A B C D E F G (b7 with regards to a major scale)
  
• Aeolian: A B C D E F G A (natural/pure minor scale)
  
• Locrian: B C D E F G A B (b2, b3, b5, b6, b7 with regards to a major scale)
  
  I bolded Ionian, Dorian, and Mixolydian because those are the most common scales you will use in jazz. They are used over a ii V I progression which is the core progression in jazz. You'll usually see a ii V I progression as a minor seventh chord, followed by a dominant seventh chord, followed by a major seventh chord. In the key of C, for example, you would have Dmin7 G7 Cmaj7.
  
  I hope this is enough to get you started!
  
  
  
  

Once you can run up and down the scales try looking at some jazz books for ideas on working the scales in other ways. My instructor uses and OnaZ likes this one. Even something as simple as playing 1-3-2-4-3-5-4-6-5-7 etc can be pretty challenging to do with good fingering (e.g. avoiding thumb on black key).

I also really like this one. It's crazy thorough; intimidatingly so.