D&D 5E Balancing factors of Armor

[AverageCitizen]

I am interested in armor-less variants core classes. Is there an unarmored class feature that is comparable to heavy/medium/light proficiency or would it have to be case by case?

 

[The Crimson Binome]

You could just give the class an AC bonus equivalent to whatever they could get by armor. For example, you could make an armor-less Rogue by giving it a base AC (12 + Dex modifier) whenever it's not wearing armor. You could even make an armor-less Cleric by giving it a base AC of (14 + Dex modifier, maximum +2).

Literally, just make something up. If nobody abuses it to get a broken-high AC, then you're probably fine.

 

[Evenglare]

See 13th age. It does the exact thing you are asking about.

 

[AverageCitizen]

You could just give the class an AC bonus equivalent to whatever they could get by armor. For example, you could make an armor-less Rogue by giving it a base AC (12 + Dex modifier) whenever it's not wearing armor. You could even make an armor-less Cleric by giving it a base AC of (14 + Dex modifier, maximum +2).

Literally, just make something up. If nobody abuses it to get a broken-high AC, then you're probably fine.

See 13th age. It does the exact thing you are asking about.

Thanks guys that is very helpful

 

[variant]

An unarmored class option that gives AC would be Mage Armor which is 13 + Dexterity modifier.

 

[Andor]

I believe both Barbarians and Monks will have unarmoured AC boosts. Plus as mentioned you have Shield and Mage Armour.

You could mix all three by multi-classing, might make for a fun character. Started out as a tavern brawler with a temper, learned some discipline while studying fighting more formally, and finally discovered his true calling as a mage, albeit a mage with a mean right hook and some real duck-and-weave skills.

 

[Tormyr]

I believe both Barbarians and Monks will have unarmoured AC boosts. Plus as mentioned you have Shield and Mage Armour.

You could mix all three by multi-classing, might make for a fun character. Started out as a tavern brawler with a temper, learned some discipline while studying fighting more formally, and finally discovered his true calling as a mage, albeit a mage with a mean right hook and some real duck-and-weave skills.

Except as noted in the AC25+ thread, you cannot combine the armor-less options. Each option sets your AC rather than adding to it. Mage Armor is 13+Dex. Monk is most likely 10+Dex+Wis. Barbarian is most likely 10+Dex+Con. These set your AC to those values rather than giving an option of "add your Con bonus." So you can't start at AC13 from Mage Armor and then add both the Dex and the Con bonus.
That being said, you can probably still reach an AC of 20 with either the barbarian or the monk. Something like a ring of protection could bump it to 21. If you multiclassed to wizard, you could get shield to temporarily bump that to 26.

A high-level wizard who took Shield as their Spell Mastery 1st level spell could pretty reliably have a 23 AC as long as they did not use their reaction for something else.