What exactly about them screams
TPK? 7 AoOs seems excessive unless you can somehow force the party into actually provoking that many (that would require reworking its entire array of feats and maybe giving it a class lv or 2).
And when you say little access to spells/ranged attacks, how little/bad is it? For instance, an enlarged fighter with a reach weapon already has 20-ft reach, which outclasses the huge elemental.