For watching, I think you have to be there to watch it properly.
On TV, the madison is unwatchable, so is the points race, in the sense you can't follow what's going on.
But I think the pursuits have to be the most boring races, they're just like robots going round and round. Time trails are boring as well, to watch.
The best to watch, live and on telly, are the shorter events like the sprint and kilo.