I grew up in Bournemouth and like many other seaside towns that HAVE survived this has become a bit nasty for other reasons in my opinion (too much concrete and too many drinks promotions). I moved to Eastbourne 8 years ago as a 30 year old and wouldn't leave for anywhere else in the UK. Brighton & London are close enough to provide you with as much party as you can handle (london on the train is just over 1hr 30 and costs £12 return off peak from the Tourist information office in the town centre) but when you want peace and some good old fashioned England I think this is where it's at.
The surrounding countryside and villiages are wonderful and don't have the pretention of Surrey or Bucks. I was bowled over when I came here how friendly the people were and how reasonable everything seemed to be cost wise.
Eastbourne has become very popular with film crews and for good reason, it's seafront has remained pretty much untouched in the last 50 years so is ideal for period dramas (like the recent remake of Brighton Rocks). And weirdly even stuff like Little Britain was filmed here.