His down throw will combo into his neutral air, it's a reliable 14%. When your opponent hits the 40% range, use his uair instead. It requires a bit of timing, but it will connect. Also, if your opponent is a middleweight/heavyweight, you can combo his forward throw into his dash attack, if and only if your opponent is really low on damage (0% till 10% roughly) you can usually also follow up with a side tilt or a neutral air. Up throw...well, I use it for his arrows, force an air dodge and up air or upsmash. His Side B is extremely useful for punishing an opponent's intended punish after you do a smash attack or any move with tempting cooldown, like his down smash. Notice that when you use it, Pit takes a step back to then lunge. That stepback is useful to dodge a grab and punish for it. Due to Pit's arm's knockback, you can effectively "combo" with it in the air, hit the opponent with the aerial version of the move and pull away from the opponent, chances are that he/she will follow and try to punish your endlag, when this happens, it's safe to go for another side B. Do not be scared to go off the stage. You have wings, use them. His fair has amazing KO and gimping potential. Also a short-hopped bair usually goes well with a following side tilt. Honestly, I really don't see how people have difficulty KOing with Pit. He has a plethora of options, and can space EXTREMELY well.