Soloing over Giant Steps chords can be drastically simplified by focusing your efforts on target notes. Complex sounding lines quickly begin to materialize by leading to the target notes using simple chromaticism.
I shared this simple method in the past, but I wanted to elaborate on it further.
I highly recommend mastering this simple method, for it is effective for creating simple lines that have strong melodic direction with harmonic implication.
Harmonic clarity is very important in jazz improvisation, however, depending on what type of vibe you are trying to create, implied harmony that has strong melodic direction can create a very interesting kind of tension.