It's true that Beguiler is a very low skill class. I'd argue that very poor skilled players cannot tap into it's potential, but just having a derp run around in circles chucking plague bombs is undoubtedly more beneficial than him doing anything else.
The combo of
2) PlagueBomb (Lay next to target)
3) Warmup Pulse
4) Fireball upon finish
is undoubtedly one of the strongest combos in the game. It allows you to instantly
deal 3 sources of your damage, all of which are above 100 (with moderate Int), to a single target, with the possibility of hitting 2 of those on other players. The damage numbers can get very absurd with this technique, but of course, it only applies to 1v1 situations.
I do not know what Kainzo originally envisioned for the Beguiler, but I know what it is right now. And that is a CC powerhouse that is one of the strongest 1v1ers, 1v2ers, and teamfighters in Herocraft. Is this wrong? Should this be changed? I don't know. But I know that adding or removing any skills will destroy the class structure, as well as the class balance. Beguiler has always been a tough one to balance, but at the end of Bastion, and the current version in Haven, I think is pretty close. Early Haven it was undoubtedly one of the stronger classes, but I quickly patched in Charisma dependencies and lower base damages for skills to alleviate those issues.
Numbers could be tweaked a bit, but I honestly think Mass is useless in its current form.
In Bastion, MassPiggify was on a 2 minute cooldown, and lasted for I believe 7 seconds. I thought this was odd, as Piggify was only 4 seconds. It seemed strange that the AoE version of your primary CC was actually stronger than your single target. It was also a "get out of jail free card", much like Layhands and old BladeGrasp.
A skilled Beguiler was able to win most fights without ever using the ability, but if he ever wanted to win for sure, he'd just have to pop MassPiggify and wait on his cooldowns. In order to rectify this, I reduced the cooldown to 60 seconds, and placed the duration below their single target version. Was this the correct thing to do? I dunno, but I still hear complaints about their strengths, so maybe...
Pulse and Plaguebomb are really my only reliable damaging skills where other casters have many more than that. The real problem is that our combo works on everything and is hardly versatile. Though I don't feel beguiler should be a Support Mage. A heavy AoE burst mage with odd cc and battle field control is unique enough on its own. Kinda unsure of Wisdom tbh, but I do notice some mana problems in prolonged fights, so I don't think its that bad.
I also want to add in that, Masspiggify and pulse have some really short ranges, after my piggify burst, you can kite or even kick the pulse. This forces us to be close-med ranged with low hp and armor.
I think your issue Victim is that you aren't really a caster player. The strongest ability any caster can have is Fireball, and their ability to consistently land it off cooldown is what determines their strength with the class. Piggify really makes it easy to get one or two off for free, but when fighting any decent player, a Beguiler must either kite until cooldowns expire, or have good Fireball usage.
I don't think cast times are appropriate on CC... I just feel as tho there will be too many draw backs.
Simply making the cool down longer might do the trick... As it gives the other player more till to kill the beguiler.
Long cooldowns promote kiting, as seen with classes like Mystic, Beguiler, and even Cleric, to some degree. A class that is forced to wait on cooldowns will resort to kiting until those cooldowns expire. I do agree that cast times on CC are not the most desirable thing though.