Besides what Amnoriath posted, I thought I'd give it a shot at making a really quick and brief (and dirty) skeleton... It took longer than I expected so I gave up and the Wizard is missing. Sorry about that. I might come back to it later.
Please feel free to use my skeleton as a skeleton for a better skeleton. Also, skeleton.
3
Rage related, core distinctive feature. Somewhat offensive oriented due to its reliance on Rage.
6
Not too powerful feature focused on either a different pillar or defense.
10
Mostly a ribbon aimed at the other pillars with minor mechanical benefits
14
Impactful feature that increases a barbarian's options
Being jack-of-all-trades by nature, their Archetype progression seems to slowly make them better and better at the role their college aims to represent.
3
Bardic Inspiration Modification
Additional Proficiencies
6
Distinctive and powerful feature that specializes the bard into the role the Archetype is trying to fill
14
Not sure, seems to patch in the holes to make them a true <Archetype>
1
Bonus Proficiencies
Gameplay-defining feature
2
Channel Divinity iconic and representative of their God/Domain.
6
Somewhat less impactful CD, CD improvement, or passive feature.
8
Divine Strike or Potent Spellcasting
17
Big ability that has a very divine/chosen one flavor.
This one's hard as the only two Archetypes are very different from each other.
2
The biggest defining feature, determines the Druid's gameplay more than any of the other classes
6
?
10
Combat oriented feature
14
Ribbon
3
Flavorful Combat improvement that differentiates a fighter's combat style
7
Ribbon aimed at other pillars
10
Minor improvement that extends the theme
15
Moderate improvement very related to their early level (3) features
18
I've no idea, some don't even get a feature here and the Champion's is pretty good...
You want to have 1-2 features that use Ki, their 6 and 11 features are more ribbon-y and not strictly combat focused (although they do have combat application)
3
Feature that relates to their Martial Arts/Flurry or grants them
6
Flavorful Utility
11
Seems to be more survival oriented
17
Offensive damage feature
3
Two Channel Divinities, one typically Offensive, one more Utility/Defensive
7
Aura or passive feature, tends to be team-oriented
15
Defensive / survival feature
20
Capstone that turns the paladin into an avatar of the powers it channels. Tends to have a few features that cover defense, offense, and utility, all while looking bad ass.
A lot of the ranger's power and gameplay comes from their archetype
3
Damage improvement that has a big impact on how they're played
7
Minor defensive feature
11
Big Damage boost (usually helps reinforce the fact that ranger can attack multiple enemies)
15
Big defensive feature
3
Ribbon aimed at other pillars but very heavy on flavor and with the second ability determines a lot of how the class plays
Ability that improves or modifies how they can use Cunning Action
9
Either a very non-combat ability that reinforces their role, or some situational combat ability
13
Seems to be another small ribbon-like feature with some situational combat application
17
Very powerful combat boost
1
A Defensive
and a distinctive ribbon utility feature that heavily sets the tone of the Archetype.
6
Powerful boost that makes the Sorc better at (or when) casting spells
14
Utility/Survival feature
18
This one varies but its generally a pretty strong ability that gives the sorc different options.
Their features usually follow the theme of the class in that they recharge on a Short Rest.
1
Passive benefit, super distinctive of the patron
6
Survival / Defensive feature that recharges on a Short Rest
10
Ribbon of a more passive defensive nature
14
Combat oriented feature. This one is considerably more powerful and might recharge on a Long Rest