I think that Pit's honestly fine the way he is.
I'll put some thoughts here based on some solid input I already read. So this certainly isn't me saying that anyone is wrong, I just think that we need to not be thinking about what buffs would make Pit more viable, but what can we change in how we use what we have to make Pit viable. The game is more balanced than people care to give it credit for, as it goes far more in depth then 1v1 default matches.
But again, here are some thoughts.
Pit is well-balanced as he is, even his upperdash (come at me my Pit fellows.)
what is really questionable and should be really fixed:
-Guardian Orbiters start up time, why? and lessen end lag if done in air.
The start up time is understandable. This move would be devastating if we could throw it out whenever. This move actually is already devastating when used based off of reading your opponent and punishing said opponent for being habitual. I surprised quite a few opponents at a recent tournament that I took 2nd in a couple of weeks ago by baiting them into a situation that they would toss out a projectile and getting the read, most of which ended in an early stock for me due to the damage multiplier.
-Up air knockback should be increased, I understand that pit has lots of jumps and could get really near blast zones to kill with his Fair or Bair, but his jumps don't get him to reach an enough height to kill with Uair! rage rarely helps here, move balance is just wrong, I just like it because it's integral in Pit's combo game 'till 70%s
This move actually has a pretty solid killing success around 140% for medium weighted opponents. And it's great for stringing together moves when you bait the air dodge. And since it takes quite a bit of priority on your opponent when they don't air dodge, it is great for racking up damage when they don't air dodge and try to drop on you. Mixing that up with a FFUSmash can result in an easy stock. If we added knockback to the move we give the opponent more time to think as they fall and less time for Pit to keep up the mind games.
-His UpB has unnecessary ending lag if you aim to the ground.. why? move doesn't hit and can't really be angled down.
I don't think this move has any reason to be used other than for recovering. That's the nature of such a solid recovery. Look at DHD and Villager- fantastic recoveries as far as distance and control- huge commitment in using the move because there is no hitbox and if used in anything else you have terrible landing lag. Also they both are in the move until it ends by either landing, grabbing an edge, or running out of time with the move. If you have commitment issues, these aren't the characters for you, lol.
-fix UpSmash hitbox, on Pit's left bow slashes but it doesn't really hurt opponent.
Pit's upsmash is a deadly anti-air, and should mainly be used for that. Obviously it helps rack up quick damage at low percents off of a down throw, but it isn't meant to just pick opponents up from anywhere and send them flying upwards. That would be way to ridiculous. It already has hitbox's in front of Pit and above him, and very little end lag for such a quick and powerful move. Adding anything else too it would honestly make it way to OP.
welcome buffs:
-even though I'm okay with this Upperdash, It'd be great if it can kill 100-120% without rage (that'd be too great though, and may get pit in higher tiers, I like him mid)
Moves got super armor and racks on some damage. Isn't the best move but it's great for mixups and can still land a kill eventually. It's great for getting out of tight spots when you catch your opponent slipping. I don't think it's a great move, but it certainly doesn't warrant a buff.
-either increase arrow power or decrease ending lag severely, also, it would be lovely to have a hitstun similar to P:M.
Arrows go hard in this game. Even with the end lag you should be getting one of two things when using these correctly- a free hit or a baited air dodge, which leaves the opponent vulnerable for more than long enough to follow up. We should absolutely get punished for throwing these out whenever.
Any windbox is good windbox and it throws opponents off pretty well as is.
-Maybe also giive Pit better mobility in the air, he has wings.
Pit's mobility in air is definitely not the greatest. But having solid arial range and priority, and still having 3 jumps he definitely isn't going to struggle in the air or recovering if you play smart.
but yeah, 4 buffs should be given to Pit without really changing his tier position.
I just think he is much better than he is given credit for currently. If you play patient, smart, and read your opponent he doesn't stand a chance. Pit can play from a distance and really shines when you get in their face. He has so many options for gimping opponents between his arrows, ariels, and Usmash. His edge-gaurding game can be disgusting (totally a positive context). Also, much like link, they really made Pit a powerhouse in this game. He hits ridiculously hard and it's fantastic. He definitely is more suitable for a more developed smash player because you just need to understand the basic mechanics of the game to make the best of his mobility in this game (which for anyone looking for tournament success this should be something you have down or are working on anyways), and he is an absolute win without any further buffs.
Don't get me wrong, I love Pit. I main Pit because I love to play Pit. So buffs would be very cool because I would love to mindlessly wreck people as my favorite character. But I don't think they are at all needed.