A few things:
Hole #1 - clear up the line to the left placement. The ceiling is too low IMHO to even consider going that way at this time.
Hole #6 - downed trees/brush in fairway needs to be cleaned up. That's a broken ankle/lawsuit waiting to happen down in there!
Hole #14 - mando sign on the big tree so yahoos don't try and cheat the horseshoe approach? I.E. Blue Valley hole #9
Hole #15 - retaining wall behind the teepad?
Hole #17 - can they move the tee sign to another location? When playing to the right placement in the woods, that tee sign on the short pad is in the line of fire for the average/casual player and is a distraction for the professional player off the long pad.
Grass OB - the flags will only stay as long as people are honest and don't pull them. How long does spraypaint last to define the OB on holes like 3, 8, 10, 11, 13, 14, 17 & 18? This is really a tournament question, but something to think about because it isn't defined for casual play very well (if the intent is to define for casual play as well).