I know that in a lot of countries foot launched micros (PPGs etc) usually don't need a license to operate, but are there any countries that have similar laws for Ultralights (the US definition) ?
but you said
I did look at the NPPL for light aircraft but I figured if I can't take a non pilot up and I can't go out of the UK then what's the point?
US Ultralights are single seaters. If you now want to fly single seaters, you can do that here on an NPPL (M).