The first thing I wanted, once I had learned a few “licks,” or melodic patterns, was to have hip lines. You need to be able to run the changes without thinking too much. Here are some steps to help you get started.
First of all, play through the tune using standard (spelled from bottom up) 3-7-9 and 7-3-5 voicings, and playing the root in the right hand. Do this in as many keys as possible, hopefully all 12!
Next, we do the same thing but use a 1-2-3-5 melodic pattern for each chord.
This is fine for starters, but, as you can tell, it’s a little awkward, because you have to drop octaves for each new root. So now, we’ll hip it up a bit with a melodic pattern for the “I” chord based on a Charlie Parker melodic idea. On the ii-V’s (Cm7-F7, Am7 D7, etc.), we’ll substitute a melodic line on the V that descends to the next root. So the resulting line is much smoother, and easier to play. In bars 5 and 6, it’s two bars on the same chord, Bb7, so I introduce an Ab in the last eighth note of bar 5, so we don’t have to repeat the Bb on the downbeat of the next bar.
Definitely come up with your own harmonic variations on this, for example, in the last two bars, Am7 D7/Gm7 F#7. And in bar 6, try Bbm7 Eb7. I also enjoy F7 Gm7 in bar 7. And you can play the whole exercise using entirely dominant-quality chords too.
There’s no shortcut for having some melodic “vocabulary” that you can run through all keys. Here are a couple of very easy patterns that might be helpful. If you’ve worked through the exercises already, the first should be very familiar. Although it’s built on the two-bar minor ii, dominant V/ major I progression, it works just fine on dominant V/major I, and, for that matter, on two bars of V, or two bars of I. You just need this stuff to help you connect your more melodic ideas. You can practice these either with or without the left hand at a slow tempo at first, then speed it up.
I like to practice these making up lines in the second bar of each lick, so we have a steady stream of eighth notes to work with. At least you have that capability, and part of your improvisational process is deciding not to play things you already know how to do. That is taking control of the music, which is what you want.