1) Not feasible currently. 'foo.bar expands to (foo bar), so you're example would expand to (x y z), or ((1 2 3) (4 5 6) (7 8 9)) where (1 2 3) is being applied as a function.
While it could be implemented, I think it would only serve to further confuse existing syntax.
2) This require some serious hackery on integers to get that to work.