The composite course at Walton Heath can be made quite long enough even for today's players. They play the Old 16th (normally a shortish par 5) as a cracking good par 4. They roll two holes together, it might be the Old 3rd and 4th, and there is plenty of space to put in new tees. The only problem comes at the end, as neither 18th hole is as strong as the rest of the course.
The length question is a serious issue. There are so many wonderful heathland courses near London which are now too short - even Wentworth West. Professional tournaments used to be held at Stoke Poges, Moor Park, Sunningdale Old, Royal Mid-Surrey, Woburn and probably others, but unless any of the new courses comes into the reckoning I don't see any of these (save perhaps Woburn) hosting another professional tournament. Happily in the amateur game the Hampshire Hog/Salver at North Hants and Blackmoor, Berkshire Trophy at the Berkshire, and Berkhamstead Trophy still attract the best players, even though none of those courses is long. The English Amateur Championship continues to be held on the sorts of courses on which we would wish to see professional tournaments: Notts, Alwoodley, Walton Heath, Saunton, Woodhall Spa in recent yars, although Bromborough was a slightly surprising venue in 2005. The Brabazon Trophy (English Amateur Strokeplay) Has been to all of these plus Deal, Hunstanton, West Lancs, although it, too, was surprising in visiting The Oxfordshire in 2005. In Wales there are the Duncan Putter at Southerndown, the Trubshaw Cup at Ashburnhm and Tenby, the Aberconwy Trophy at Conwy and Maesdu and the St David's Gold Cross at Harlech. It's much the same story with many of the top amateur events in Scotland and Ireland on first rate courses.
It's curious to note that the PGA Championship (which is now the BMW Championship) has been held at Wentworth on an annual basis since 1984. In the years immediately preceding this it had been at R St George's, R Birkdale, St Andrews, Ganton, Hillside and R St George's. Now that's a more inspiring list. Funnily enough, when it started out it went to some interesting venues such as Pannal, Maesdu, shburnham, Coventry, Dunbar, Western Gailes and Thorndon Park among others.