Indeed, if I'd been spec'ing Perl 6 interpolation, I think I would have removed all other interpolations in favour of a single 'interpret the block and substitute whatever it produces in its place' construct.
Oh no! Perl 6's new quoting mechanism, with everything based on a single C<Q> and a bunch of adverbs is just breathtaking: it is at same time simple, intuitive and powerful as familiar constructs like C<q> and C<qq> will remain very much the same as in Perl 5 and a terrible amount of more flexibility will be available at the tiny expense of appending a semicolon and a few letters. Or in some cases no colon at all and a single letter.
For me, the ability to have my editor highlight interpolations, (without resorting to running a second OS as an editor:), would more than make up for the slightly less convenient syntax it would require for the simple case.
Oh well, that's hardly a problem for me so we definitely see things from two very different perspectives. Personally, I find too much syntax highlighting to be distracting, but when I find it... ehm... desirable. (Speaking of strings, in current Perl, e.g. when the necessary evil of a string eval of a considerable amount of code is needed and then I use q{...} or qq{...}.)
Yet it seems to me we could still have the best of both worlds: if e.g. C<qq> implies :s, :a, :h, :f, :c and :b you may still stick to only interpolate {...} expressions when you want them to be syntax highlighted, and your editor may do a good job of doing so.
Or if you want to stay very strict, then you may get into the habit of doing:
macro qbuk { Q:c:b }
