Here's the schematic.
I'm glad I might've actually helped someone else with their problems, hopefully. I suppose the thing that gave it away on my set was that I messed with the drive trimmer and it made the linearity worse, so I figured I could make it better with more capacitance.
Thanks for your interest in my case. If you ask me, it's very important to keep these old things actually useful. I'm getting the vibe that many here like to restore tv sets to the way they were, and even use them that way, but that way is already long gone. If we want to preserve these pieces of history, I feel like it's paramount that they can actually be USED for some functional, present-day purpose (even if I personally don't plan to watch a whole bunch of tv on this set). You know what I mean?
Let me get down from my soap box here.
Anyhow, um, as for the shadowing, I don't think there is much to do about it. I'm trying to picture it my head, you'd have to move the beam over. Wait, is that even possible? Like, you can bend the beam, but can you just nudge it over? I suppose maybe... a different ion trap? Perhaps if you mess with the deflection outputs... Say, add a resistor and a diode in parallel with each other, but in series with on one side of the horizontal output. That would force the horizontal to favor one side, I think. idk, I'm just spitballing.
I was thinking, for the DC restoration, when the video signal goes higher (negative-er), it could power a transistor base, and that transistor could be used to pull the video drive down closer to zero. It would probably take an immense amount of fine tuning. It would need a specific capacitor to average out the video signal, and it would probably need a diode to prevent it from having a feedback loop (or whatever you'd call it, when the transistor lowers the voltage going into its base and then unlowers it, etc).
My other thought was to bypass the whole video section and use solid state electronics to do the whole job, but that seems like a bit of a cop-out. Not to mention difficult.