A couple of thoughts. Do with what you will.

First, it's nice to get reads, but it really doesn't mean much. Producers read many scripts for every one they buy. Agents reads many scripts from un-repped writers for every writer they decide to rep. So take a deep breath. Pat yourself on the back because you're clearly writing loglines which make people want to read your scripts, and that skill's not going anywhere. But do not feel like you have to charge down this opportunity right now if your material isn't ready.

If your material is good enough, this opportunity won't matter that much. You'll have more. And if your material isn't good enough, then this opportunity doesn't matter, either ... nothing will come of it. So take a moment. There's no rush here.

I can't tell you which of these scripts to prioritize, absent more information. Whatever you do, don't leave these people hanging. Some version of "Hey, thanks for your interest. I've decided this script needs some work before I send it out. I'll let you know when it's ready," goes out to both people.

I would probably veer towards the script for the producers over the script for the agent, but that's a very small edge which would be dwarfed by my own feelings about whichever one I was more excited about.

I have to admit that I feel like you're positing a false dichotomy when you ask, "When I'm rewriting, should I focus on making the script as solid and ready to produce as I can or is it better to highlight my voice and point of view?"

Make it as good as you can make it, to YOUR taste. Why would that be contrary to making it "solid and ready to produce?" The only reason why someone is going to buy this script is if they fall in love with it. Trying to guess what they want and be that ahead of time is unlikely to work. Can you give me an example about how "highlighting your voice" would make the script less "solid" because honestly, I'm not sure I understand what you mean.