The beach would seem the obvious place to go when you have some experience, and aren't terrified of losing your Mavic in the sea, but initially I would be heading inland towards the green belt of land just behind and around the main estuary. You have 2 small airports (Seething Airfield and Beckles Airport) in the vicinity, so you should avoid flying within a mile of each of those, and you are probably best staying well away from any built-up residential areas, where the wi-fi disruption might very much compromise your available control range.
PARK EAST looks like it might be fine, as do the fields around OULTON BROAD and ROTTERDAM RD, though to be honest any recreational playing field that doesn't have 'no drones' signs up will probably be OK, as long as you are flying within the CAA rules (no higher than 400 ft, no more than 1500 ft away from you, 150 ft away from people and buildings).
Here's a link to UAV Forecast. Pop lowestoft into the target area box at the top, and expand the map to see where the airport perimeters are.
Cheers for the help bud..
had a small flight today at one of the parks near Olton broad and all was fine did not send her up too high or far..
Recharge batteries and went to fly again but now have a warning up saying rear right vision sensor not working and needs repairs..
not good considering iv only had it up once..!
You could send it back to DJI, who will almost certainly fix it for you, but it'll be a 6 wk+ adventure while that gets sorted out if you send it back to them.
Or you could use your 14-day no questions asked guarantee to return to the unit to where you bought it, either requesting an immediate swap or your money back. I think I'd try that if I wanted to resume flying as quick as possible...