2) Redo-last-change. In Vim, if you make a change, pressing "."
will make the change again. Is there something analogous in Emacs,
aside from defining a macro?
Either C-x M-ESC or C-x z, depending on your requirements.
You probably mean C-x ESC ESC or C-x M-: . C-x M-ESC simply quits my
emacs. But both are not doing what '.' does in vim. With vims . you
can repeate commands like “replace next three word with …”, “indent 5
lines”, “append … to line” or “replace rest of line with …”
(where … stands for some text). This is not possible with emacs
because there is no implicit grouping of inserted characters, so C-x z
repeats the last character typed, which is completely useless.