I have never visited Poundbury and am unlikely to so other than what I have seen on the news I am clueless. Although I would hesitate to call by the specific term New Town which had/has a specific place in English/Scottish/Welsh law.
New Towns were primarily for overspill from major conurbations like London and Glasgow and many other cities which had suffered under the oppression of Nazi bombing raids in the Second World War, and from the urban clearances which preceded but mostly followed the war.
As has been said about Coventry and London, for example, what the Luftwaffe started the planners finished. ("the planning department of the London County Council, whose unofficial motto was Finishing What the Luftwaffe Started")
So when entire neighbourhoods were torn down the people had to go somewhere. New Towns were conceived as places they could be relocated to despite breaking up local culture and relationships, and despite being many dozens of miles out in the countryside.
Some New Towns, particularly in Scotland, have lost the committees (QUANGOs really (QUAsi Non-Governmental Organisation = QUANGO, sometimes as QUasi Autonomous Non elected Government Organisation) ) which drove them forward and kept them going.
Milton Keynes, of which I can speak quite freely, it being just a few miles from me, is one New Town I know very well. I'm writing from personal knowledge, not google. New city really because just before our late beloved Queen Elizabeth II passed on she made Milton Keynes a city.
Some parts of Milton Keynes are still being built, and there is still a large amount of the city undeveloped, but some of the original housing stock is in an awful state, and some parts of Milton Keynes have some of the most deprived areas in Britain. Most buildings originally were council houses, fairly recently virtually all of the housing has been privately built, some very expensive. Most of the neighbourhoods are middle to lower middle class and working class.
Milton Keynes was built originally as a series of pseudo villages (every estate has a name by which it is known) on a grid pattern, linked by high speed (70 mph) arterial roads and roundabouts, and laced together by a network of "red roads" - narrow pedestrian and cycleways which never cross the arterial roads at grade. Mostly underpasses by a few overpasses. Each pseudo village was to have local shops and other amenities, with major shopping centres linked by buses and Central Milton Keynes which is mostly shopping malls and office blocks.
Crime rates are very high in some parts of Milton Keynes and unfortunately some of the red roads have become the haunts of some of the less pleasant members of the community, especially the underpasses.
If you intend to look around Milton Keynes it is wise to know where you are going - appearances aren't everything, some of the most heinous crimes in recent months have been in ordinary looking estates - and know what you want to see...
The most famous residents of MK are the concrete cows. Every conceivable shop - pretty much - is in MK Central so no need to go to London for shopping. Many of the middle class residents do go to London to work, trains are very crowded at rush hour. Milton Keynes has three train stations - Wolverton (site of the former railway workshops), Milton Keynes Central and Bletchley, from north to south. Like everywhere in the financial crisis bus routes are being cut back and prices raised. MK wants to be world leading electric vehicles but many of the few chargers are out of order, and the self charging buses the town arranged for the city has cancelled.
Parks are extensive and many follow the Grand Union Canal as it passes though on its way to London. There is an indoor ski slope with good snow.
Milton Keynes was started in 1967, some buildings have been demolished
Is there anything in particular you'd like to know?