Sigh.. okay so let's go hauling back old Veigar with an ult that scaled harshly and scaled also on a targets AP and give him mana back so that he never has to leave lane and leave his q to stack.
Veigar where he is at the moment is perfectly fine and balanced. His aoe got removed from an instant cast to a delayed ability that nearly anyone can escape from because of how telegraphed it is that he is going to drop the damn thing. If you are an AP laner you can just either buy a zhonya or banshee veil and hope to god the veil is up in time to block it or you can zhonya in time to negate it if you are far enough from the ult to react cause of its travel time. If you are an AD laner than either get yourself a guardian angel and hope your flash is up to dodge the aoe or get yourself a qss for his cage to escape or buy an edge of night and time your active right.
In norms, Veigar is placed at 22nd with a 12.04% pick rate according to op.gg and in ranked he is placed at 52 with a 7.65% pick rate across all ranks, this shows that his selection rates are too small too worry about in needing to give him an update but out of that tiny selection group are the niche players that can play him real well and just have better reactionary timing or frames to win lane vs you on skill alone or get extremely lucky via camps or in team fights. Veigar is also in a position where so many items allow to you to live through his burst, that he might as well have a 0.01% pick rate because of people using said items or too many champions who are given free mobility that they shouldn't have in the first place end up escaping via dashes, leaps or jumps.