As @Grady says, removing leaves could result in more harm than good. Some people prune the tops of tomatoes and peppers to keep them within a certain size. I don't do this with my peppers - they have space, and I just let them grow. More plant = more peppers down the road.
In the case of peppers (and most fruiting plants), removing fruit can enhance growth. This varies - for example removing peaches from a peach tree will result in larger fruit (same resources going in to fewer fruit). Peppers flower and form over a period of time (unlike peaches where a tree's blossom occurs all at the same time) - so the presence of peppers on a plant can inhibit the growth of new flowers and fruit. So I remove peppers when they are ripe enough to eat. Having too many on the plant will reduce flowering and formation of new peppers. Also the longer they are on a plant, the more likely you will risk pest damage (individual daily risk is small, but if they're on the plant twice as long, then they're twice as likely to get damage).