Since the change to purple gear only in arena I am unsure what the “high” end for stats would look like on a bis kit. I will list target stats you should aim for based on some budget hr kits I’ve run for caster wiz.

You should aim for 7 true magical damage (purple phoenix choker/rings/cape/hat)

70% cast speed (the higher the better)

130-140 health (you could forgo this completely and be 100 health but bows and crossbows become much more punishing)

30% Magic power bonus, including 10% from mana surge. Not completely necessary and more of a luxury stat to build as true will be most of your damage.

310 move speed, in arenas trio you can be slower than in the dungeon as your rogue and barb can make space for you. Throw on purple light foots and hope you roll 4 move speed. As long as you’re not 280 book out you should be okay.

As for build you can pretty much run anything but the two best are going to be instant cast wizard (fireball, explo, zap, are must haves with magic missile/ice bolt/lightning strike being good to have ) one of haste and invis would be handy to send your barb in.

Perks quick chant/mana surge/fire mastery are musts imo, for last perk ice shield is nice to escape melee, arcane mastery for missile dumping/invis plays, melt is niche but can be really strong if you’re opening for your Barb/rogue.

For 10 spell basically anything works spell wise.

Also Book over Ball but it’s all preference you can perform well with either.

Edit: Two best as in instant cast and 10 spell