Wow, what an interesting topic to me!
First, I think you're pretty darned smart, Brian, to take this to the next level. The type of canning you used to do is called "open kettle" in USDA lingo. It's not recommended for shelf stability (but great for refrigerating) because open kettle does not create a true vacuum. If the safety seal punches down, it does so only because the ingredients have cooled and contracted, but the oxygen in the head space is still there, and will remain there until a high heat process (water bath or pressure) is applied and the molecules exit the headspace through the 2-part lid.
As long as you stick to high-acid foods, water bathing will be enough. BTW, I'm privy to many commercial applications of food safety. You may wash your jars and then store them on trays in the oven, on low heat, until you need them. The risk is this: if the oven heat is cranked too high, there is the chance that the glass jars, when introduced to the cooler kitchen air, will crack, or worse, explode in the cook's face. All commercial canneries keep their jars hot (but not immersed in water) before filling them.
I teach canning using USDA consumer methods, with a few commercial methods thrown in. Many students are worried that they will encounter relatives (who don't use USDA methods) who'll give them a hard time for processing their jars because "no one ever got hurt." I'm going to tell you the story I tell them.
"Let's say every day I drive to Kroger. Might be for a lot of groceries, but it might be for a cup of coffee. Kroger is my second home, only 2 miles away! I relax on the drive, because it's a quick and pretty, and I've never had an accident.
So one day I tell my kids, don't buckle up. Heck, we're only driving to Kroger. I can drive there in my sleep, and nothing has EVER happened to me -- or us!
So my kids jump into the back seat with no seat belts.
Halfway to Kroger, a car approaches mine. The driver is texting and doesn't see me. He suddenly swerves into my lane and crashing into my car head on, flipping it. My unbuckled kids go flying out the window and are killed. (OK, I HATE this part of the story...)
I didn't expect that driver. I couldn't control him. If I'd only taken a few seconds to buckle in my children, we'd all be safe."
Of course, the driver is botulism. It is unpredictable and undetectable. At least you can smell and see yeast or mold (the two other bad boys in canning), but botulism cannot be seen or smelled. It is a natural force of nature that may be present in low-acid foods, and can only be killed in ultra-high temperatures brought by pressure canning.
Yeasts and molds are killed by a quick water bath -- easy. After all, good fruit is hard to come by, and who wants to take the time to cook a fabulous strawberry preserve in June, only to find gross hairy mold enjoying it immensely in February?
Sounds like you enjoy high-acid canning. So simmered lids, room temperature bands, hot jars, hot ingredients, and water-bathing for the time allotted by a qualified canning recipe will keep you and your family safe, while allowing you to have delicious, shelf-stable items on your shelves. Sorry, this is more information than you asked for, but this is a topic I savor... Let us know what you create!