From the perspective of a public/semi-private course golfer -
1. Recognize that times change. Every course I play seems to offer the same 10-15 item lunch and dinner menu, but I've hardly ever seen anyone eating anything but burgers and fries. It sure seems that fewer and fewer public/semi-private type golfers are coming in early/sticking around afterwards anyway, so why go to all that extra effort (and waste) in the (now too large) kitchen and lounge? How about specializing in one simple menu-item - say, a pea-meal bacon sandwich, either with cheese or without? Let it be your 'signature'.
2. Don't sink too low. It saddens me to think of course owners using/offering those golf.now green fee specials. Set a fair price and stick to it - the kind of golfers who will come to your course only if/when your $40 fee is available for $30 are not the golfers you want, and won't be the kind to come back anyway (unless you go even lower). I get annoyed at those golfers too - come on: if we can afford $30 to play golf we can afford $40, and nickle and dime-ing all the courses in town will eventually mean there are no courses left.
3. Talent helps. My modest 1970s semi-private has wonderfully playable greens, and there's never been a hitch. The expensive golden age private up the street 'lost' 6-8 greens over two consecutive winters. I wouldn't know how many different factors are involved here (and I'm not naming names because of it), but the super at the first course seems to be managing better than the super at the second.
4. Find little things that are nice. I think an important thing in getting repeat plays is that golfers find the over-all experience of being at a course a pleasant one. Little things: clear signage and flow and friendliness from the parking lot to the first tee; maybe a minute or two more between tee times (and announce them over loudspeaker as they're coming up, with our names...On the tee now at 9:30, the Jones group; on deck off at 9:41 the Smith group; the 9:52 Baker group, you're up in 20 minutes); maybe the truck/machines/crew cleaning up bunkers or getting to changing the pin locations can wait until well into the late afternoon if not done by early morning -- I think few of us mind a messy bunker or yesterday's pins if it means not watching maintenance crews scrambling to stay out of the way/stay in front of us all round long.
5. Recognize that things change (Part 2). I hate to say this, but I think the days of the pro-shop at these public/semi private are gone for good. Save the space and the outlay of capital - very very few of your customers will be buying golf bags, let alone new clubs, from the local course/pro shop ever again..and not shoes or wind-breakers either. Widen the selection of the golf balls you offer, and sell tees and gloves.
Modest changes, realistic ones - cut costs a bit on one side of the ledger, and have happier (potentially repeat) golfers on the other side.
I wish all the course owners good fortune and good ideas.
Peter