Definitely two for resale! Modern bathroom designs don't need a huge amount of space if you are clever about your configuration. The best way to get around the space issue is to include a shower-only (unless you need a bath for kids etc).
A lot of my renovation plans have been inspired by looking on real estate websites to see what other people have done in their room layouts. If you have a small space, then check out new apartment developments who need to be smart when it comes to space