If you put any type of path alongside the hedge you're going to have to keep the hedge trimmed so you can walk along it...that will immediately tidy things up.

Up to you, then - slabs sunk in so that you can mow over them, a complete 'crazy-paved path', a gravel path with brick edges or the edging tiles that stand on end so you can strim agaimst them, those would all look good. I would imagine it depends on cost and available labour, too, as to what you go for. I wouldn't go for a bark path, though - the birds tend to scatter the bark everywhere.

Think about the width before you decide, too.