1) I think it would be cool if HB studios implemented a feature that is now available on the Aboutgolf high end golf simulator. It allows you to crouch down and when doing so, the putting surface raises up a couple feet below eye level and you're able to read the greens. How about implementing this feature into putting in The Golf Club? I don't think any game has done it yet..
2) Power Meter - Standard stuff but I do think there are times when a golfer needs weigh the risk/reward and give it a little extra, off the tee. How about a tapping button function that, unlike Tiger Woods games, doesn't max out when the ball icon fills up but is only limited to how quickly you can physically tap the button, therefore it's kind of on you to see how much more you can get on your drives.
3) Caddies. I know this is reaching at this point but down the line, I think caddies would make for a nice option... can steal one from TW and have the option to go with a recommendation or your own call. Change clubs, caddie animation goes to the bag, take out a different club, cleans club after shot, etc.
4) Multiple colored golf bags & staff, cart, carry sizes.
5) I would love to one day play a golf game that gave the user the option to ride a cart down the fairways/paths and actually have to locate your ball based on your typical club distances (could have a yardage meter that counts down the further down the fairway you drive).
6) Weather/time of day and the effects that go with it (lighting, dew, temperature changes).
7) Ocean course theme

Down the road and I'm sure they're eying this up anyway, but real players with their real caddies and real equipment (ball selection: low/high spin, shafts: spin/launch characteristics, shaft lengths - more distance vs more control, etc).
9) Smoother backswing/downswing transition and animations. Seems kind of jagged and slow as it is...
10) Fix the across the line at the top swing all the players have with the driver.
11) Confidence meter (based on prior shots and round momentum) Ups the ante with risk/reward shot opportunities.
12) Real, Licensed Courses one day.
13) Custom camera angles including ball cam.
14) Take a page out of MLB The Show's book and really nail down all the subtleties and nuances of golf animations pre, during and post shot. Including unique pre-shot routines, waggles, etc.
15) Practice Facility (driving range, short game area, putting green, etc)
16) Different types of grass with different affects based on course and course location, weather, time of day.
17) 1 and 2 plane swings with a indicator track or line that you have to match with the joystick (miss inside - draw/hook, miss outside - fade/slice)
18) First Person Swing Cam. Would be difficult to implement if done well could add a different dimension to golf games.
Just some suggestions for you guys that I think would really take things to the next level. Some are definitely unrealistic at this time but perhaps down the road. Cheers. Looking forward to the console release.