Alright, I'll try to share what I know on this MU.
At the beginning of the match, you're going to have to play very smart. For now, focus on camping and wracking up damage. Make good use of your Arrows, and don't try to assault him too much. If he gets close to you, use your jabs or any other move that is fairly quick. Once you push him away, try and escape to a safer position if you can. Keep using Arrows and wracking up damage. Make sure to save Pit's kill moves, as you'll need them fresh once you get Ike to a killing percentage. If you get caught in Ike's jab combo in this part of the match, DI out of it immediately. You don't want to reach over 100% before he does. And just be careful of Ike's side B and any other mindgames, as you don't want to get to a high percentage before he does. Also, start taking note of your enemies habits and strategies, as you'll need to find an opening once you get Ike to a high percentage.
Once you get Ike to a higher percentage, start looking for openings to use your kill moves. Once you find an opening, attempt to use one of Pit's kill moves to KO him. If you miss, it's fine, but once you miss with one move twice, try and switch to another kill move. Nikenick's suggestion on Power Shielding Ike's Fair isn't a bad one, as it can open Ike up for punishments. If you get cornered and need to shield, try switching to Mirror Shield. Even if it doesn't reflect Ike's moves, it's a nice, constant shield that you can use. Since you will also be pushed away if Mirror Shield doesn't reflect Ike's moves, it is also good for spacing. But try not to get predictable with Mirror Shield, as once Ike finds out that he can grab you out of it, things can get ugly (I've noticed that not many people know that you can grab Pit out of Mirror Shield. I suggest using it against players that don't have too much Pit MU experience). If you are also at a high percentage, try not to go in too much. Make sure that you have a surefire way of hitting him if you're at a high percentage. If you're at a higher percentage than him, keep using the strategy from above (using Arrows, using jabs or another quick move when he gets close, and keeping your distance). Once you get Ike to a high percentage, start looking for an opening. But still be careful, as you may be at a point where even the final hit of Ike's jab is deadly. Also, be on the look out for Ike's infamous jab>jab>Utilt combo. It can be fatal if you're over 100%, and it can kill even earlier if you're at a stage with a low ceiling. If you're at a high percentage, stay out of Ike's jab range. As once you get caught, there is little chance of escaping a jab>jab>Utilt combo.
Once you take Ike's first stock, you're probably going to be at a high percentage. Revert to the strategy of keeping your distance and using Arrows. You're prime goal at this point of the game is to wrack up damage so it'll be easier to KO Ike once you do lose a stock. If you're at a low percentage, that is excellent. But, don't go rushing in and attacking, still concentrate on wracking up damage and keeping your distance. The lower you are at percentage, the more damage you'll be able to inflict before you lose a stock. If you get Ike at a killing percentage and you still haven't lost a stock, go ahead and go for it. But since your moves are most likely stale, it'll be harder for you to KO Ike.
If you were the first person to lose a stock, this battle just became much more difficult for you. Keep your distance and wrack up damage, but be extremely careful, as Ike can wrack up a lot of damage if you mess up spacing, and you don't want to end up at an even bigger disadvantage. You're going to have to exploit your opponents weaknesses to a fault here. Make sure to punish any predictable moves, and be on the look out for mindgames. Once you get Ike to a Knock Out percentage, try and head for the kill, but be extremely cautious, as you don't want to get even more damage. If you are able to take his first stock before you lose your next one, revert to keeping your distance, and wracking up damage.
The endgame is important. If you have the advantage, that's great, keep it up. But, if you're at a dissadvantage, you're going to have to play even smarter.
If you have the advantage, keep wracking up damage, and keeping your distance, but don't be too afraid to look for combos. If you have a stock advantage, you can loosen up a little, but be on the lookout for any lethal moves. If you're on the same stock, make sure to keep a percentage advantage, and punishing any predictable movements. Make use of your multiple jumps, and try to fake out a laggy move from Ike. Once he's open, drop down and ues any aerial you'd like, this strategy is also good to use throughout the battle, but make sure not to get predictable with it.
If you're at a disadvantage, you're going to have to play super smart. Just concentrate on increasing Ike's damage, and saving your kill moves. If you can get the lead again, try and mix up your strategy, as the camping may have gotten predictable. And again, be careful of any killing moves, such as Ike's jab>jab>Utilt combo. The best way to avoid things like this is to stay out of range, and bait a laggy move from him. You would have to play super smart, but if you can read your opponent, the battle should be winnable, as long as you don't make any lethal mistakes.
Try and stick to a strategy similar to the one I mentioned for the beginning parts of the game. But, try and switch to another strategy midgame. A very good thing to learn is using different strategies, and never getting to predictable. Change strategies if you think you've gotten predictable, and switch strategies to fit your opponents playstyle. This is an invaluable technique, and I suggest you learn it. As changing your gameplay mid-game is a great way to confuse an opponent.
For stages, try to pick a stage with a high ceiling, as it'll help you in surviving any of Ike's Upwards attacks.
I'd say this MU is 50:50. Pit's amazing defensive abilities cancels out Ike's strong offensive capabilites. How the match will turn out will mostly be up to the players skill.
Well, I hope this helps ^__^. Don't know if I made any sense. But, I hope this is helpful ^__^.