A big problem with ultimates, beyond them being too powerful, is that they dominate the playfield for so long. With 12 heroes each with their own ultimate, the game becomes dominated by ults more or less at any (relevant) time of the game, because they last so long.
Remember Mercy’s original Valkyrie? You could just sit there disheartened while nothing died for what felt like an eternity, trying to at least build your ult. At least Valkyrie right now is not as strong, but that feeling kinda remains.
Junkrat’s tire is another example. While that thing runs over the map, god knows where, all the enemy team can do is run for cover and stay on the lookout for a low-percentage chance of shooting it. That tire can potentially run for a very long time, dominating the fight until it executes.
Moira’s ultimate lasts a long time as well, and it is really limited what you can do against it, as no barriers work and she is very hard to kill because of her mobility and the strong self-heal of the ultimate. That means that what you can do is usually only to run for cover and wait it out.
Of other long-lasting ults I would like to point out Orisa’s that does however have counterplay, making it a bit fairer, Soldier76’ which also last a quite long time, Symmetra’s wall, that takes an eternity and is as good as impossible to break, Winston’s supermonkey form also lasts very long (although it can be countered with damage). Roadhog is also quite long lasting and dominating while it lasts.
Zenyatta’s ultimate can also be argued to be a bit too long lasting, as you feel quite useless as an enemy while it is running - you can just sit there and wait it out. Ashe’s Bob takes a small eternity to execute and takes quite some effort to kill, especially if the enemy healers try to prevent it.
Ultimates with very short durations are Tracer’s which of strength is barely stronger than a regular ability (Storm Arrows are arguably as strong), Reinhardt’s that although it is very strong, is quickly over again. Reaper’s is fairly short (and painful!). DVA’s ultimate is also quite fast, and so is Pharah’s.
Compare this to for example League of Legends.
I will admit that my experience with LoL is fairly limited but I do remember that most ultimates were far from as dominating and long lasting.
- Hecarim could make a charge that put fear on everyone right in front of him for a very limited time (1-2 seconds?), usually affecting only one, sometimes two enemies.
- Lux would shoot a giant laser beam through the entire map. You would get a warning sound so you could react, and then it would be over in a few seconds.
- Ahri’s Spirit Rush gives her three short-range teleports allowing her to rush an enemy. It would be over fast.
- Jax got a passive damage bonus for some seconds.
- Lissandra casts an AoE, that damages and slows enemies for a few seconds. Alternatively she could cast it on herself and it would work like Mei’s Ice Block (in general Mei seems to be inspired from this hero).
- Ashe fires a giant arrow through the entire map that stuns and freezes. The closer the enemy, the shorter the duration (maybe 1 sec stun if close), meaning it is much harder to follow up if it hits further out.
- Garen has an execute-ability, which is a single strike and then it is over.
- Jinx has an ultimate that fires a rocket (instead of an arrow like Ashe). It has an execute-ability like Garen’s strike.
There are longer-lasting ultimates in the game, but they are not so dominating, because they usually are in an AoE that can be avoided. LoL is not so focused in one area as OW, so you can avoid an area without becoming completely irrelevant.
IMO OW could benefit from having ultimates that are shorter in execution. Right now the long duration of alot (most?) of ultimates is saturating the game to a frustrating degree, as it is often hard with standard hero abilities to do much against them.
Why not have short ultimates instead? They can still be powerful, but at least get it over with fast, so the “normal” game can continue.