Arcane warrior wasnt really overpowered as most people think.
You had downsides (which were kinda heavy). The plus-sides, coupled with gear, stats and abilities specially designed for the ultrastrong auto-attacker AW made it very powerful, but it required a very distinct specialization.
In other words, saying that an AW was overpowered would be like saying crit/assassinate rogue in DA2 is overpowered. Or that a min/maxed glass-cannon mage is overpowered.
These are all good builds with strengths and weaknesses, the reason they work are customization and specialization when it comes to planning and building a character. If arcane warrior wasnt strong despite using attributes, gear, specific spells etc - all to make it work - then something would be wrong.
you don't need to cater to anything to effectively utilize arcane warrior specialization; just passively using the equipment, you become a tank that runs over student protesters.
in origins, cailan's arms set really helps with fatigue. In awakening, considering the best runes are often glitched to be unusable or in short supply, the stacking fatigue rune becomes a highly viable choice for augmenting plates on mages.
the core concept of arcane warrior is that it offers the one thing that mages lack and allows them to outperform the default class within the game.
in terms of gameplay balance, arcane warrior and blood mage should've been awakening specializations.