Man, where to start.
You could wipe half of them out.
Lets start with big ones. Baseball goes. Handball goes. Beach Volleyball goes. Im torn on Water Polo and could go either way.
Anything that involved synchronization goes. Swimming and diving etc
Want to have different distances for different guns in shooting? Then combine them so, for example, a air rifle participant has to shoot at all different distances (rather than specialise in 1). Cut the number of medals available in shooting by a lot.
Swimming? Great talent and exciting, but it isnt a legit sport IMO if their are medals for different strokes. No medals for hopping or backwards running in track. Swimmers get from A-B as quick as possible with whichever stroke. Fantastic effort by Phelps but a track athlete could never match the tally because the opportunities are not there.
The walks (20k etc) ? GTFO
How many sports involving bicycles? road race, velodrome, BMX and different distances. Pick a bike event and go with it. How many different things can be done on a bike? Make them do them all on the same bike. The sport changes because the bike changes? Arse. It should be about the athlete.
Ping pong. It isnt a sport. It is a social activity. Badminton, Im torn on.
Oh and there are loads more that probably need to go before some of the above do.