John - it all depends on what you are looking for regarding being near the coast. Llantwit Major is very close to the sea but there are high cliffs in the vicinity. The nearest beach would be either Barry which is in my opinion a non starter or Southerndown to the west. Unfortunately east of Port Talbot is very industrialised - for scenery and unspoilt coastline you should ideally be west of Swansea. Porthcawl is not too far away from the site but again it is not the best of resorts - Coney Beach end of the town is very dirty. Aberavon Beach is approx. 40 minutes by car away and has a lovely stretch of sand but there is heavy industry at both ends of the beach.
Inland there are the town centres of Cardiff, Cowbridge, Bridgend, Pontypridd, etc. Don't bother visiting Bridgend as the best thing about this town is the road out - boutiques, estate agents, banks, building societies, charity shops, cheap jack shops, Tesco and Asda all aplenty if you like that sort of shopping. The Gower coast is just over an hour's drive and the coast of Pembrokeshire is approx. 2 hours drive so I would venture west when ever possible.
Sorry if I have sounded negative but as a resident here for over 40 years it would not be my choice for a holiday.