Her superiority seems to have been retained long after. I don’t know that she’s more resiliant to real Green K, but it was noted that she’s immune to the synthetic variety that still bothers Superman.
Well, Kal-L was pre-Crisis Earth-Two Superman, which wasn’t as potent as an Earth-One KRyptonian. Speculating based on the cover of the next issue of Infinite Crisis, I bet he and the current Superman are a roughly equal match.
The Flash family’s steamrolling of Superboy is questionable in my mind at best. If he suddenly decides to push against them, I’d think they’d go splat. I’m chalking it up to kinetic energy manipulation - essentially they’re forcing velocity on him, not just pushing him.
As for his descent into madness, look for Infinite Crisis Secret Files, coming Real Soon Now.
Ma Hunkel as the Red Tornado also showed up for a couple panels in the very first appearance of the JSA back in All-Star Comics #3. (She tore her pants coming through the window and had to leave.)
Sabertooth’s not Wolvie’s father in 616, either, FTR. That was shown to be a lie some time back (after I stopped reading Marvel regularly, so I’m not sure when, but when I came back, it was definitely shown to be a lie).