I flew hang-gliders for quite a few years before switching to sailplanes and I have one paraglider flight logged.

I would say that hang-gliding and paragliding give you more the direct personal experience of flying than sailplanes and will be less costly overall. In Europe, there are many sites available for foot-launch equipment on mountains served by ski lifts and in Britain you have lots of opportunity to work ridge lift. The equipment is portable and there are many clubs. However, be aware that a paraglider is an inflatable wing - which means deflatable too! Your undercarriage is also not very crash-resistant.

Sailplanes open up the possibilities of really long cross-country flights, an experience that many of us find to be a great challenge.

I recommend trying both - it's hard to know what you will find the best challenge.

Mike