Anything that has toe welts is going to be overkill for almost all of the cascades. Keep what you have and when you get ready to climb the taller peaks reconsider and either rent or buy something heavier.

If these are the "minimum" requirement for the mountains I want to do then they are probably not for me. I wanted to go with a step down from double plastic - just one step down though.

Easy enough to do. La Sportiva Nepal Evo or the Scarpa Mt Blanc will do that. La Sportiva Trango Extreme or Scarpa JORASSES PRO GTX will as a well. The Batura and Phantom Guide Series is truly one step down from a double plastic boot but not the best summer boots for what you want to do. But yes, what you have is the minimum in summer for the mtns you have listed. A tiny step up from the Trango S EVO GTX. Which is not a common boot on Rainier or Baker. But it is a very common boot in the rest of the Cascades for climbing and difficult approaches.

My question is more about the fact that boots that accept automatic crampons seem to be in "another class" and it is that class of boot that folks are suggesting for Rainier. I have had people tell I /need/ double plastics for Rainier and Shasta in July and August. I was hoping to find a high quality boot that would serve me well that was not double plastic.

You don't need a plastic for summer trips on these climbs but you will want a dry boot. Plastics help with that especially if you are new to mtneering . But the down sides are steep.

I want to get them soon so I can do day hikes at my local mountains throughout the year to get in shape and break my boots in.

The more rigid the boot the more your feet get broken in not the boots. Plastics are generally comfortable on your feet first time you lace them up. But they will never be comfortable doing day hikes in compared to a lwt hiking boot. Neither will the leather boots that are a step down from plastics like the Mt Blanc or Nepal Evo. But you can walk in them to get on the mtn. Most won't hike in them.