Hi
Its true Clevedon has a better selection of older houses, but its new build explosion was in the 70s/80s, while Portishead is having its now. The links givemeaclue gave you show the best old houses Portishead has to offer at the moment (and they've been available for a while..)
In comparing Clevedon and Portishead, I find that Clevedon is a town of two halves - "upper" Clevedon (cos its up the hill) has the nice houses and smarter shopping street (selling nice clothes and homewares, nothing really practical, but with a few nice restaurants and beauty salons), while "lower" Clevedon (cos its at the bottom of the hill) has the estate agents, supermarkets, and A LOT of charity and discount shops. You can tell the difference. The large Victorian houses in Clevedon have often been turned into flats (because they are massive)
Portishead only has one high street with a nice mix of useful shops and new tapas bars/coffee lounges. And Portishead has a marina, which is filling up with nice yachts...
Portishead's seafront is in a separate "Lakegrounds" area (with boating lake, tennis club, open air swimming pool (in the summer), play area, cricket pitch, cafes), whilst Clevedon's seafront is along the road, but it does have a lovely pier, and some nice Georgian houses.
The Curzon cinema in Clevedon is fab we go when we can, and I often bump into my Portishead friends there, so its used by the whole area.
We relocated here from Reading 6 years ago, but it wasn't a proper relocation as DH was brought up in Portishead, lived in Clevedon as a young man and has roots here.
Either town would be fab - please come!