And there it is, the common misconception used to fuel one of the Ekko hating arguments.
Most of the time Ekko has to CHOOSE whether to use his ultimate for damage OR for repositioning. And no it wouldn't more likely be in a more favourable position. Most of the time when you ult to survive a gank you ult back in the lane, towards the Enemy's tower and farther away from actual safety (for example). Sure you can still escape due to movement speed and slows, but just leaving that bit of information you seemd to have forgotten to mention when saying it's in a more likely favourable position.
When you ult out of a teamfight, same concept, if you ult for survival you ult away from the fight, hence getting out of the fight and not helping your team.
If you ult for damage you are smack in the middle of everyone and unless you did a combo ult into pre-cast W for stun you will be very vulnerable.
Ekko's ult is a fantastic tool, no denying that, but it is hard to use effectively and in addition to that most of the time you don't get both of best worlds.
You either use it to damage, or you use it to escape/reposition.
You can't list both at your convenience to make your point more valid.
And while Kayleìs ult doesn't hit a "massive" area for damage, she can simply stand there dealing high damage without risk of death for those 2 seconds.
Tryndamere might be "balanced" (lol) around his ultimate existing in that state. It still doesn't mean it's a healthy mechanic.
I'd take Ekko's ult any day of the week against the other two. It requires way more setup than the latter 2.