If you are looking for a smaller tree that is really different, Kindred Spirit Oak may provide just the characteristics you are looking for.  Kindred Spirit is a hybrid Oak very similar to Regal Prince Oak, but presents an even narrower profile.

The deep dark green leaves of Kindred Spirit Oak have a handsome shiny surfrace, resistts leaf tatter and usually stays nice looking throughout the growing season.  While Regal Prince Oak has become much admired for its lovely form that matures to 50 ft. tall by 20 feet wide, Kindred Spirit is the narrowest Oak cultivar we have encountered, being rated at a mature size of 35 feet tall by 6 feet wide.

The English Oak xSwamp White Oak parentage of Kindred Spirit Oak gives it great versatility in a wide range of soil conditions, which is always a big plus in landscape beds where earth moving equipment may have greatly disturbed natural soil profiles.    The very narrow character of Kindred Spirit also allows it to be used as  a focal point in a creatively designed landscape.