If you have a lot of sigs, Void or Namor are you best bets. Personally I say Namor, but a ton of people will say Void. But in my opinion, Namor doesn't need high sig as much as Void It really comes down to personal preference. You have it 100% backwards. Void just need awakening and benefits from the higher sig. Namor prettymuch needs hihgh sig to reflect the fun/interactive stuff that matters.
If you have a lot of sigs, Void or Namor are you best bets. Personally I say Namor, but a ton of people will say Void. But in my opinion, Namor doesn't need high sig as much as Void It really comes down to personal preference.
Void, no contest. Doom doesn't need his sig and Namor should only be awakened if you can take him to max sig. Awaken Void but leave him at sig 20 until your AA is at least sig 120