So it has to be technically difficult or complex to be good, this kind of opinion makes me laugh. Personally I look for more than just complexity in music. For me Opeth can either be totally awsume (Black Water Park, Damnation) or totally shit (Deliverance, My arms your hearse). I understand why metal lovers may not like damantion, personally I think its one of the most beautifull albums I've ever heard. Deliverance is shit because of the repedativeness, it could have been good if the songs were shorter. Wreath in particular is a disgrace. Black Water Park is their only other album I would consider to be good. Morningrise is brilliant in parts but overall its boring.
By the way knowone will take you seriously if you use language like virginal ass.