Don't get hung up about poor public transport - it's not as bad as people make out. Most of wales has good bus services, and the rail service along the coasts is at least every 2 hours in summer ( a bit less in winter.) Also consider cycling (if you don't mind hills) there are plenty of cycle hire places. I often carry a medium format kit complete with tripod on my bike. In my opinion the blinkered 'can't do anything without a car' mentality is destroying our landscapes - try photographing the Llanberis pass on a bank holiday!

Rob