I think something like Historio.us might be the way to go. They give you 300 bookmark slots free when you sign up, which is a fair amount even if you import old

I think something like Historio.us might be the way to go. They give you 300 bookmark slots free when you sign up, which is a fair amount even if you import old bookmarks. As I inch closer to the limit, I can see myself just biting the bullet and buying the monthly subscription. It's just a few £s to avoid a lot of hassle and continue using a useful service. However, I doubt I would have paid from day 1 when there are free alternatives (which may even have been just as good, I'm not sure. I may never know.).