All of Romeo's points are valid. It's ultimately up to you on whether you want to run Adramalech or Sersiryx, they do completely different things.
Adramalech (along with Ring of Fire) might be a plausible answer to swarms. If you are trying to chip away at your opponent with curses and they're attacking you a growing number of creatures then eventually they'll out race you. You may want to lay off the curses for a couple of turns if you see your opponent casting so many creatures, then save that mana for Adramalech because he eats foxes for fun. Once the man threat is out of the way you can transition back to your win strategy.
Enchanter's Wardstones won't protect your enchantments forever, but they may protect them on the round that you cast the stone. After that they're just useful for gaining major mana economy. I don't particularly like to summon them in the opening, instead I'll cast them right after or before I reveal an enchantment I want to keep around. Counting your opponent's mana for the current and following round is crucial to making such a strategy work.
As far as Mage Bane and Ghoul Rot go, they won't be curseweaved if your opponent dispels them, So you'll need the extra copies for that. If you think that one creature will live by one health then Chains of Agony isn't the worst option out of Sectarus since it will finish them off and then you can curse weave. Finally, an AMAZING curse to return to your hand is Rise Again, I've both won and lost games that swung wildly in someone's favor because of that card.
Glad I could help, thanks for joining us on the forums