Hi Chris,
if you want to get a yacht when you're back in the UK the Potty! is really a good choice. It's cheap - £ 850 - and very light, very enjoyable on sand or hard surfaces.
The basic Ludic is pretty expensive - almost twice - but it's more sturdy, has a bigger sail - 4.5 sqm against 3.6 - and if you want to sail on grass the fiberglass flexible axle is really a bonus. Easy to sell at a good price if you want to take a bigger yacht.
Someone I know use to pack the Potty in a surfboard bag

then fold it, the Ludic has its trolley, but the sail has its own bag, so you can't hide everything in the boot.
Blokart is quite fast on the hard, but sailing mainly on grass I prefer the Ludic. It's not so cheap - at least not here in Italy - but for sure is a masterpiece of engineering if you want to get a plane. Don't forget a bigger community is often a bigger fun.
Maybe before you're back you could keep on enjoying the Manta Twin, it's really made for the dry lakes
Ciao - Enrico