As others have said you don't want to get in a loop of endlessly redoing things.
As a reader I want to keep progressing in the story, I don't want to keep reading the same scenes over and over with nicer art. Nice art might get me to check something out but the story is what keeps me coming back. If you pause your story to redo everything, you risk alienating your fan base.
That said, as a creator I am thinking about putting together a PDF of the first chapter and prepping it for printing. My old art looks a lot different than my new stuff and I do have the urge to just redo the whole thing. But, I am making a list of priorities that will make the printed version better. That does include redoing some panels here and there, but I have decided I can only do that stuff if I keep moving forward on my comic. I have to keep putting out a page per week and write the next chapter. Knowing that, it keeps me from massively rewriting plot points, redesigning characters, and messing with continuity. Then, once the PDF gets done, then I have to drop it, I can't revisit it. It takes willpower but finishing the story is the most important thing to me.
I suggest you figure out what the most important thing to you is, telling the perfect story? or finishing your story? and let that guide your decisions.