My wife and I are in the process of rennovating (aren't we all? :-),
and we need advice on a bathroom.

The master bedroom used to have a small (~4'x4') half-bath in one
corner. The other side of the wall is the back hallway; across that
hall is an equally small bathroom with a shower (!), sink, & toilet.
There's one room off the back hallway which would be a great guest
bedroom if there were a decent bathroom nearby. The door to the master
bedroom is right next to the main bathroom, so it didn't seem
worthwhile to keep the small half-bath, so when we redid the master
bedroom, we expanded the walls of the half-bath and closed it off to
the bedroom, with the expectation of opening it out into the back
hallway & putting a shower, sink, & toilet in there (and turning the
other bathroom into a closet, which would be very nice).

The new bathroom is now 60"'x90", since that was as much as we felt we
could take from the master bedroom; the door has to be in the shorter
wall because of layout, but is not placed yet. We've seen designs for
5'x8' bathrooms with the door in the middle of a long wall, which
doesn't help us much. We talked with a guy at Home Depot, who put
together a couple of potential layouts for us, but I wasn't convinced
that they were ideal for our situation--I think he was just using stock
fixtures, and I think there are smaller ones that could be ordered
(though I haven't verified yet). His basic design was sink by the
door, shower & toilet on the far wall. Many of the bathroom planners
I've seen online are also limited to stock fixtures (or ones by
specific manufacturers) and/or don't let you know if a given layout
would actually give one room to maneuver about.

So, my questions: where should we look for smaller fixtures? Is there
any option short of making plywood cutouts and putting them on the
floor that would help with planning the layout? Should we consider a
pocket door--would that buy us anything, and is it possible to install
it without stripping out the new master bedroom wall (I'm ok stripping
the back hallway walls down to the studs, if need be)? Are there any
other options we ought to consider?

Thanks,
-David