Undergrowth is a good thing, and is good risk/reward. I think though you should remove any dead trees that have fallen over if that's the case. As long as it is growth(living) then leave it there. Removing trees that have fallen down (especially over gaps) can make the course look better and also be safer, so people aren't climbing on them (although it is fun...). Another thing you could do is trim fairways. One thing I really hate is the luck factor.
The local club is adding in a pro pad at carroll marty (Ames,Iowa) on hole 4. The route is tight with a 10ft wide fairway, and reduces to about a 4 ft gap 3/4 the way down. It's a short hole of about 200'. We went down and trimmed off all the low hanging branches that just stuck out to swat down discs. The line is hard enough to hit without 1 twig hitting it and screwing up an otherwise beautiful shot. That's the type of trimming that should take place, not removing rough.
The local club is adding in a pro pad at carroll marty (Ames,Iowa) on hole 4. The route is tight with a 10ft wide fairway, and reduces to about a 4 ft gap 3/4 the way down. It's a short hole of about 200'. We went down and trimmed off all the low hanging branches that just stuck out to swat down discs. The line is hard enough to hit without 1 twig hitting it and screwing up an otherwise beautiful shot. That's the type of trimming that should take place, not removing rough.