Croatia has less Brits than other places, but it's definitely becoming more popular with Brits.
I've been to both Dubrovnik and Pula. I think when you go makes a difference. We went to Dubrovnik the week before the season officially starts - not everything was open but it was fab. We stayed in the walled city itself which few tourists do. The upside was we were in the city before the cruise ships landed and there were less of them. Getting up early we roamed the city which was virtually deserted apart from the cats. In the evening the cruise ships all fucked off and most of the tourists went back to their apartments / hotels outside the city walls which again was brilliant. If we'd had been there at the height of cruise ships it would have pissed me off. People getting off the ships didn't even know where they were and that is just ignorant. We did islands around Dubrovnik and a trip to Mostar. There was one day we went for a boat trip where they caught fish off the boat and we had it for a barbecue.
Pula was lovely for a couple of days. We went in August I think - it was the middle of the film festival. We watched a film (Spiderman! Which wouldn't be my choice but it was the film the night we arrived and we were hiring a car the next day) at the amphitheater which was wonderful. We hired a car and did some of the islands before going to Plitvice and then back to Pula.
And that would be my trip for Croatia. Don't just stay in the cities. They are great for a stopping point but there is some amazing stuff just down the coast which is less crowded (busy yes but definitely not rammed). Certainly the islands were much quieter. And there's plenty to see inland too.
If you want a beach holiday, don't bother. You ruin it for the rest of us!
Reading through the thread at mentions for a load of other places, it does read like people go with the top check list of things to do and wonder why it's not great. It's not great as it's the conveyer belt. You don't have to go off the beaten track by any means but going to places which the locals visit more often if you can is definitely the way to go.
We tend to do the 'go to things' still but go, get them done as quickly as possible and then find something else to do rather than have the entire day doing that one thing. We definitely are not ones for a relaxing holiday.
I'm looking at what we have in mind for our next holiday which is three days away and I'm seeing that it'd be a week for most people! That would bore us though!