What do you mean, a _weaker _ Veigar E, when it deals damage? Does it not stun or stay up as long? In any case, a charge system would be rather oppressive for an AoE hard CC basic ability. Maybe you could have it work like a Viktor W, but it damages instead of slowing?
In any case, silencing your teammates isn't a good idea, because it would lead to extreme feels bad moments. Besides, silence is a powerful tool, so maybe you'd be better off with an AoE interrupt (a bit like Viktor's R), which could work on an empowered basic ability. Though I can't say I understand what you mean by "a cone" the size of a Ziggs R, when the latter is a circle; do you mean a cone even bigger than Cassiopeia's R?
If I can suggest something based off of what you've presented, assuming this is for a basic ability, you could place down a zone that deals DoT (say for 5 seconds) which you could reactivate after a short period (say 1.5 seconds) to end the DoT (maybe dealing one last burst of damage) and stun everyone in it. This is a lot more simple, but what you described was more of an ability with multiple parts (the result of one "Q" would place three DoT zones, then a silence zone, and overlaps would cause combination bonuses) than an ability that evolves (which stay more or less the same, but with added effects).
Anyway, I think huge DoT zones combined with mass CC is a bit much for a basic ability.
