Parry isn't really viable for a mage because it requires 80 dex to be most effective, meaning a serious compromise on your intelligence which wouldn't be acceptable.
Wrestling, or a weapon skill such as macing, fencing or swords, is an absolute requirement for a PvP mage as your combat skill is a direct factor in determining whether other people will hit you using melee. I'd say anything less than 120.0 skill in this area is unacceptable. The only real exception to this rule is if you're using a weapon with a "mage weapon -skill" property. Necro/Mage characters, who have particularly cramped templates, often use mage weapons and make up the skill that they lose elsewhere, or they use artifact items with "mage weapon -0" property on them, such as the
Staff of Pyros or the
Staff of the Magi.
Lastly, yes it is worth taking Spirit Speak above GM. It is the damage and curse duration modifier for the Necromancy line of spells and if you're looking to maximize your offensive effectiveness in this area then the higher SS the better. Spirit Speak is to Necromancy what Evaluating Intelligence is to Magery. 120.0 skill would be good to aim for in this area.
Hope this helped. Take care.