Ultralights are not meant for travelling so I assume compass isn’t necessary (though I don’t know exactly why). These planes can land just about anywhere (better than the best STOL aircraft) without engine power so I guess running out of fuel isn’t as life threatening. But yeah, how hard can it be to add a simple magnetic compass?
There are some extremely good freeware and payware helicopters you should check out. However, the Top Rudder Solo still remains the best sight-seeing craft at low-speed, low-altitude, and ideal weather conditions. It has no obstruction of view when looking down and you can enjoy the views with little attention to aviation as you would a helicopter.