chuckle The -really- nasty confrontation would be Andrew Granger and Ron. Molly and the Trio is going to be, I'd venture a guess, -very- hazardous to Molly's elf-image and opinion of herself, as well as having the potential to be physically hazardous. It would be interesting to compare the reactions of McGonagall and Snape to the Trio.
I rather suspect that if/when Ron tries anything, he's going to be lucky to end up alive, for some values of "alive" (not necessarily sentient, though). I get the impression that Harry & Hermione have been taking steps to hone their abilities while Ron's spent the summer raging.
Author's response
Oh, you've given me such an interesting idea concerning young Mr. Weasley... I must think on it to see if it would be in character...
Ron is going to be unhappy for the forseeable future. Ginny to, but mostly Ron.