Id personally go for Luton, they have good support, even though they plummeted a few years back, many still attend, so there is bound to be good money coming on down that end, problem is a fair few conference clubs have come into money, and Luton although on paper seem to have a good squad, they never make it. Think with a bit of investment they would get back up. Not to mention the players they tend to bring through the youth system.
Leeds united without any doubt, miles ahead of everyone else.....It was and still is bad management with them and if anyone can afford to write off their debt and plough millions into the club for the right players then even though they wont make any money for 6-10 years they should get the glory years back as one of the top 4 sides in football....