Clubs in general depend for their survival on their members, not visitors. Enhancing the benefits of club membership for existing members and making it more attractive to potential new members is the main priority IMO.
Visitor income can play a useful role in keeping annual subscriptions affordable and so attracting and retaining members, but no more than that.
The typical 25-45 year-old guy has a full-time job, a mortgage, and a young family. In all probability he can manage to play golf for half a day per weekend - any more than that and he will be deemed to be taking the piss and is destined for a painful divorce. In this, golf is little different from any other sport; hubby will be allowed his half day to play football or rugby, go to a football game, play cricket, etc. The other three-quarters of the weekend he is (quite rightly) expected to spend with his family.
The problem with this is that golf club membership is just not an attractive proposition for most people playing once a week for maybe 35 weeks a year. A relative newcomer to golf needs to play more often than that to see any meaningful improvement in his game, meaning that disenchantment is likely, and 35 rounds a year works out at upwards of £30 a round. Good but not great value for money.
I see no reason to change the traditional 18 hole competition format at weekends. The difference between a 3 hour round and a 4 hour round on a Saturday morning is neither here nor there in the great scheme of things.
Where imaginative thinking needs to come in is in offering members the opportunity for EXTRA golf midweek, and more specifically in the evenings.
Just as those guys who play football on a Saturday afternoon will reasonably be "allowed" to attend training sessions on maybe a Tuesday and/or Thursday evening after work, so golfers have the clear opportunity to negotiate with their loved one a little extra golfing time without compromising family life.
For six months of the year there is a clear two-hour plus window of opportunity from 5.30/6.00pm for a game of golf. If clubs could lay on some kind of organised competitive structure over an appropriate number of holes on a Tuesday or Thursday evening I am sure it would prove very popular with many of the "once a week" guys described above.
It could just tip the balance for some guys between making club membership an attractive proposition and it not being so.
It would also help if rounds of other than 9 or 18 holes could count towards a CONGU handicap. The maths can't be that difficult, particularly if we're talking 12 holes. Gaining a proper handicap is probably the biggest attraction of being a club member rather than an itinerant golfer.