As for gigs in Dover...No, I don't think there is much, it all tends to be at the Louis Armstrong. There are some at the Swingate Inn, which is, I think, between Dover and St. Margaret's Bay. Never been to either. Used to go in the Eight Bells a fair bit. After 8pm, it's not so nice, and some of the local alcoholics that go there send shivers up my spine.
Canterbury is much, much better for gigs and pubs to visit.
Never linked Folkestone myself. I grew up in Dover, grew up to hate it, as well as my usual visits to Folkestone to get myself pummelled by physiotherapists, and get teeth ripped out by orthodontists. Thankfully, I moved north of the River last year, and now reside in a village in Essex, in the middle of nowhere ;)
Congratulations on your engagement and impending wedding. We're getting married too (but no date set yet). Have a good weekend :)