As others have mentioned, just get a 7 or 8 speed RD bicycle; bigger gearing range gives you more flexibility with speeds. The deurallier bicycles are really no more complex that the IGHs, its just that the IGHs put all the gearing inside the hub where you can't see it. In fact, with all the gears exposed, I'd say a deurallier'd bicycle is easier to work on than an IGH bicycle.
FWIW: I use an old early 1990s rigid MTB with a 1 x 7 drivetrain as my cruiser bicycle.