For pure AA at 65, the 3 Ak'Anon Strike Force tasks at the Farm camp is hard to beat. But I wouldn't stay just there, if you really want to see good and challenging content at that level and slightly above.
Alot of Luclin zones are great at that level, Greig's End probably the most popular and easiest for the amount of xp at that level, as well as descent loot and tribute items, and some twinkish items as well. The same for Acrylia Caverns mentioned by Bijou, it's just not quite as popular, and a little further of a run. Sanctus Seru may be an option, and working on the Arx key (if not at 65, I've heard of Mage's doing it at 70 or 75 relatively easily). Maiden's Eye is good if you missed some of the 50s spells, and xp isn't terrible at 65. Umbral Plains I'm unsure about for a Mage at 65, but maybe plenty doable. For melee I tend to stay away from there until 70+ when I can slaughter pretty much everything without much worry, unless passing through to Vex Thal, or need something particular from there.
Alot of PoP content is challenging at 65. I can't remember any spots in particular atm that are great for Mages there (trying to think of Pet Power items and clickies and the like). The ornate armor clickies are ok, but not as great as for other classes, as they're spells you already get.
From mid 50s to 70, I usually spend some time working DoN progression. There are lots of good focus augs you can get from the DoN merchants as well. And the progression AAs are very nice.
I think there is a groupable pet power item in TSS, but can't recall it atm.
Runed Diamond is a very nice aug, that can be quested at 65. There quite a few good augs in TSS that can be quested or dropped;
Emerald of the Oasis and
Orb of Mystic Fury as examples. Some of the group armor quests have nice focus effects on them as well, but the armor is 71 req. level (
Tenish's Silk Armor (part 2)). (EDIT: The chest clicky is nice as well).
TBS has
The Sweeper for a pet power item, as well faction work needed for spells.
Most of SoF quests are 70+, but a few are available at 65, such as the 3 farm tasks, and a few other sub-quests for the face aug (
Model XLII Spatial Temporal Oculus). There's quite a bit of descent drops in SoF though for 65+.
The DoDh spell arc missions are good to do 65-70, and there maybe some descent drops. I know there is a pet power item in DSK from
Arylon.
EDIT: Ooops! I had skipped OoW expansion. WoS, especially murks are great AA xp, and of course, if you know a GM Jeweler (EDIT: and GM Poison Maker or Alchemist), the possibility of OoW augs, that can be upgraded with focus effects. MPG is descent, and there are some augs there, but I can't remember if any are great for Mag, but most likely a few are. At 69+ RSS is excellent AA spot, and good spot for quite a few descent drops, but again, I can't remember if any are excellent for Mag, as the ones that come to mind, are the AC augs. These 3 zones along with Noble's Causeway are good for farming runes for spells as well. NC is really good xp as well, but less so 65+.
Hope this helps some.
Yther Ore.
Edited, Oct 21st 2011 10:26am by Yther Edited, Oct 29th 2011 6:41pm by Yther