Oh, what a fool am I!
Literally the day after I finish this blog, the 2600-daptors that I ordered a few days prior arrived. These little beauties let you use original Atari sticks on modern hardware via USB (you will need a printer-style ("a-to-b") USB cable but those are like $4 on Amazon.)
Combined with good joysticks - like the pair of Epyx 500XJs I got off of Ebay for cheap - and you have a much improved gaming experience. In general I'm not a "has to be on original hardware" hipster, but these games were really designed for this kind of control, not the NES-like and old-school Gravis pads I used in making this blog. (You could probably write essays on the change from joystick to gamepad culture, and the implications in terms of popular styles of gameplay - not to mention how interesting it is that a predominantly right-handed culture has formed a preference for game control via the left thumb.)
I had looked into the original stelladaptor but it was no longer being made, and am kicking myself for not finding out about these earlier. (Also, I learned the hard way to avoid the Retrolink Atari-USB Cable - it seems like a cool idea, allowing 2 connectors at once, but I couldn't get it to play nicely with the various emulators I was trying to use.)
(Also, avoid the Atari-like PC joysticks - I got a set to run with my Atari 2600 game Loaded4Bear - one came broken, and the others lasted about ten minutes of gameplay. It's not very often that I say "this product is garbage" but it's pretty close to literal truth in this case.)
Again, a hearty endorsement for Tom Hafner's 2600-adaptor ii - and any decent Atari controller you can find on Ebay, either the classic CX-40s or something with microswitches, like the Epyx 500XJs.