We have just moved back after 5yrs as we were not happy there - although there were good points about it obviously and I know there will be good and bad points about life in the UK again. I have been loving it so far, which is probably an initial high before everything gets mundane. We have never had any family near us since we had the kids (apart from the odd visit from relatives) & that was one of the aspects we moved back for. It won't be hands-on family support for us, just the opportunity for the kids to spend time with extended family on the odd weekend visit & events like Christmas.
One of the things I am enjoying is the variety of things to do with the kids - so far we have been to a woodland wildlife park, a reindeer centre, a lighthouse, a windmill, a castle, the beach (sandy ones & pebbly ones!), a pier, a medieval fayre, a village fete and we have a long list of other stuff to do. I never found there was much to do where we lived other than playgounds, indoor play centres & beach unless we travelled into the city. Here we have those & seemingly more variety & can still travel into the city for big museums & attractions. This is not just for the kids but for me too as I get fed up going to the same places with them all the time!
Also there is a children's centre nearby with free activities for the kids like gardening club, music, messy play, toy library etc
The advantages for us moving back outweighed any potential negatives like economic situation etc when making the decision. Both moves were paid for by DP's job so that helped too! There is no easy way to make the decision so good luck with it!