Thought Experiment:
Would Veigar, do you think, be more healthy if Event Horizon was his ultimate?
Having been an avid Veigar Enthusiast since season 3 the problem I see him constantly running into seems to be that, because his combo is so reliant on his E up until ~60 minutes, it always happens that his E either takes up too much of his power budget, or isn't allowed to take up enough.
If Event Horizon were moved to be his ultimate and had its Coolness Factor appropriately tweaked, I imagine that would mean Dark Matter could also be adjusted to work better as a standalone ability rather than just being a damage nuke that relies on CC to function.
I guess the question here though is, should his current ultimate be powered down and moved onto his E, with maybe some thematic or functional changes to differentiate from Baleful Strike, or should he get a new E entirely, something that lets him better play up his Zone Control themes?