Tessarael
Adventurer
AC 12 Light armor + Strength modifier should be on par with AC 10 + Dexterity modifier + Wisdom modifier, particularly once you have access to magical armor. For a point buy character that maximizes defense, the unarmored Adept can have AC 16 at 1st level with Dexterity 16 and Wisdom 16, vs. AC 15 for the armored Adept with Strength 16, so it is a 1 AC difference.
Also worth noting that Brutal Defense doesn't prohibit using a shield, so if you pick up shield proficiency somewhere, your AC will be significantly better too.
Also worth noting that Brutal Defense doesn't prohibit using a shield, so if you pick up shield proficiency somewhere, your AC will be significantly better too.