Can provide the all-important contrast necessary to refresh your palate and make you want more of the rich stuff. In recent years, Eurocentric haute cuisine has really embraced pickling (which has always been a central part of Eastern cuisine).
Watery vegetables like cucumbers are best when simply salt-pickled, with acid added only right before serving. Salted vegetables get funkier and more ferment-y the longer you leave them at room temperature. You can experiment with varying degrees of the kimchi/sauerkraut effect to find a level of pungency that suits you and your milieu.