Hiya Lars,
I can't comment on Wolverhampton, but the Kent Marathon, starting and finishing in Margate is a very well organised event (130 finishers last year).
It's described as Flat/Undulating and is mostly flat in the second half along the coast. There's loads of detail on the Kent Marathon thread.
The course itself is mainly coastal and I'd describe it as a back-to-back out-and-back. The first half heads East along the coast through Broadstairs and turning round at Ramsgate with the half-way point back near the Start. The second half heading West takes you along the coastal promonade to Minnis Bay with a short excursion inland. The finish is in the same small park as the start with plenty of nearby parking.
It's also one of the cheapest marathons around at only £8 affiliated in advance.
Whatever you decide, have a good one!
Scotty
Last year the goody bag contained a medal, mug, t-shirt and some munchies. Excellent Value!