They will look a bit fluffier in a few years.  The age they are at
right now is the most gangly looking age for a cat, I think.

My black cat has hair exactly like that- longish but not too profuse. It is
the perfect amount of coat for a longhaired cat as it is easier to maintain
than Persian type coats. You will get nice long hair on the tail, back of
the rear legs, and neck ruff but not too much in other areas. So as long as
the cat is on a decent diet and you brush a couple of times a week you won't
see too many hairs floating around your home.

Length also depends to some extent on your climate and whether or not they
are exclusively indoor cats. The length of the daylight (or artificial light
if indoor animals) regulates the shedding cycles, so outdoor cats will see
longer hair in the winter and shorter in the summer (in the northern
hemisphere anyway) and indoor cats will remain relatively uniform all year
round.

And spayed female animals see less hormonal cycle induced shedding, and thus
carry more uniform coats year round than non spayed animals.

Enjoy them however they turn out!

-Toni