This is probably apocryphal, but I'll share it anyway. Please bear in mind I'm paraphrasing...
When asked about his mastery of solo (chord-melody) playing, Joe Pass said: "Many people think of notes, I think of melodies. Just as when we learn to speak, we don't think of letters, we think of words, then phrases, somewhere around there, we inject inflections, and so on. So, in reality, I'm not playing a solo, I'm kinda giving a speech on a subject I know very well. Just as I wouldn't give a speech reciting the ABC, I would not just play a scale because the notes seem to fit..."
Since I've ever heard that from my guitar teacher (a long time ago, in a ...), my entire approach to making music got shifted... It's not about scales and speed. It is about SAYING SOMETHING...
More directly to the OP, I would start by re-stating the theme. Heck, repeat the whole melody line on bass. That's what Jaco would do (To begin with...

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