Suits have become rather complicated and mod-intensive compared to what they were back then.
The 3 most common PvP mage templates, at least on the field such as Yew Gate, are Mystic Mages, Necromages, and Pure Mages. Each of the 3 have their own variations such as
Mystic Mage
120 Resist
120 Mage
120 Eval
120 Myst
120 Focus (Focus is the Eval for Mystic spells)
100-120 "Skill"
Some people go 100 Ninjitsu for animal form to escape ganks when dismounted. Some people go inscription for the sdi bonus and other benefits. Some go spellweaving for some extra field fighting viability. Some purely go Meditation as without it your mana regen will be a bit low and if an enemy Necro Mage Evil Omen > Mana Vampires you, you'll be quite useless for a bit.
Necro Mage
120 Resist
120 Mage
120 Eval
105 Necro
120 Spirit Speak
80 Poisoning
55 Med
Is the most common Necromage template purely for PvP I believe, with slight variations. 105 Necro is just enough to get you to cast 100% the useful PvP spells such as Wither, Strangle, and everything beneath it. 80 Poisoning is because with a combo of "Evil Omen > Poison" you'll inflict Lethal level poison on your target at close range. Making it difficult to cure. Without evil omen, Resisting Spells on pretty much every template makes other players difficult to apply poison on.
Pure Mage
120 Resist
120 Mage
120 Eval
x
x
x
Pure mages have the benefit of reaching an extended SDI cap in PvP, which is raised to 30% compared to only 15% for "mixed" mages. You get an extended SDI cap by only have one "magic" skill group as your skill. So you can't have 120 mage and something like Necro and still have the boosted SDI. (You still need to get enough SDI stat on your items to reach this new cap) The skills that will remove the boosted SDI cap are
Necromancy,
Mysticism,
Focus,
Ninjitsu,
Bushido,
Animal Taming,
Musicianship,
Chivalry and
Spellweaving.
Pure mages come in many different flavors as you might see if you run around some of the bigger PvP hotspots.
Variations include but are not limited to:
120 Resist
120 Mage
120 Eval
120 Weapon Skill
100 Poisoning
120 Med
-Used w/ a weapon that can inflict Infectious Strike. Does not focus on using the weapon for damage but for having a reliable method of applying poison.
120 Resist
120 Mage
120 Eval
120 Parry
120 Wrestle
100 Inscription
20 Skill (If you are human it doesn't really matter what you put here)
-Highly effective template on the field due to the high amount of dexxers and stealth archers.
and so on.
Now, in terms of suits. You have a limitless amount of options, but regardless of what you decide to do you want to make sure you hit certain stats. The most important are 100 LRC, 40 LMC, 45 DCI, 2/6 casting, 25 Hit Point Increase, 15 or 30 SDI, and all 70s Resist. If you are not going a wrestle mage/melee poison mage then you will need a mage weapon. So a weapon imbued with -15 mage weapon will allow you to have the equivalent of 120 weapon skill, which is absolutely necessary in terms of defense. To make up for the skill negative, you need +Mage skill on your suit. This is most commonly placed on an imbued ring or Crystalline ring.
Other mods you will want on a suit is things like Enhance Potions (50%), Casting Focus, Mana Regen (Depending on Template but more is always nice), Health Regen, Damage Eater, and some other mods I can not recall off the top of my head right now.
If you feel you are rusty at mageplay, the Mystic Mage is one of the easiest PvP mage templates to play, the most common, and the most versatile when field fighting and working in groups.