My site is back up, after a brief interlude: I moved hosts, because Gandi doubled their hosting costs. I'd left it quite late to renew, because up until now it's just been a case of ticking a box and paying money, so I didn't have much time to shop around.
I chose Krystal, because they use green energy and their procedure for transferring my domain seemed simple (there was a German hosting firm I was recommended too, but that one said something about filling in a form in a PDF and it looked horrendous).