> Perhaps I accept that annoying space after bQ and the like [...] You don't need to. Do ":help abbreviations" in vim, copy the function Eatchar (which is given as an example there) to your .vimrc, and then
:iabbr lQ \[lq]<C-R>=Eatchar('\s')<CR>
:iabbr rQ <BS>\[rq]
(The last one assumes you always type a space before rQ, which
then gets eaten by the backspace. Of course, this might be
improved by testing whether it really is a space or not, and
only deleting it if it is.)
