I know that part of the world inside out.
If you're going to Wellington regularly then it would be better look on the south side of the M5.
On the north side traffic problems can get dire with the A30 and A303 plus the area is largely a soulless wasteland compared to the bits closer to Devon.
Taunton's a bit of a non-entity of a place, but fundamentally fine. It's alot bigger and busier than first impressions might suggest and the traffic's appalling.
Bridgwater is unquestionably a dump as is Yeovil and they're both a long way from Wellington (an hour in Yeovil's case)
Tiverton's a solid town but somewhat bland and down at heal. It is one of the cheapest spots to live in and is close to many nice areas.
Bampton is about 10 miles from Wellington. It has some beautiful Georgian houses but is completely and utterly lifeless and slightly sinister with it.
Milverton is about 4 miles from Wellington and has some beautiful houses too, but it's also dead and filled with some strange characters.
Williton and Watchet are both within the distance for Wellington. Watchet's cheap and on the up but it does have a rough mini Bridgwater edge to it. Williton's pretty much a junction on the way to Taunton and not much else.
Cotford St Luke is a 'new village' between Wiveliscombe and Taunton. It's been built with some very nice houses but I'm not sure if there's much of a community, maybe not even a shop.
Bishop's Lydeard is a more vibrant place just beyond Cotford St Luke. It backs up onto the Quantock hills which are stunning in places.
Wiveliscombe has a nice feel with plenty of interesting shops and it's only 6 or so miles from Wellington.
My vote would be Dulverton. It's beautiful, a real community with plenty of shops and some brilliant eateries but only about 2000 people. It's on the edge of Exmoor with masses of lovely spots nearby. It's about 16 miles from Wellington. The coast is 20 miles away to the north and it's 25 miles from Taunton, Exeter and Barnstaple.