We do have many archetypes, but most of them aren't as good as a select feel. My point is that the best deck of the 28th archetype will be worse than the 8th best Vehicles decklist. Having 10 Vehicles list will be boring, but having 30 different archetypes will lead to some subpar lists towards the end, even if they rae the best they can possibly be.
I get your point, but is the 8th best vehicles decklist really distinct enough from the best in its colour without being strictly worse? And if it's strictly worse, why even play it?
Anyways; here's what I'd pick for top 30-ish:
-Vehicles (Mardu, Esper, (Boros))
Not 100% sure if Boros is not just a strictly worse version of Mardu. Haven't seen Esper yet, but that would've been an archetype I could see exploring if I fire Duels up again.
Rakdos Vehicles is listed as Rakdos Aggro - Artifacts/Vehicles.
-Rakdos Aggro (Artifacts/Vehicles, Madness, Vampires)
All of these archetypes are distinct enough to deserve their own mention.
-The Energy/Constrictor group (Gruul, Golgari, (Jund))
Gruul Energy Aggro and Golgari Constrictor Midrange (this includes +1/+1 counters) are definitely top 30 archetypes. Jund I'm less certain about; that deck could just be better off cutting one colour.
-Counterspell-based control (Dimir, Esper, Izzet, Jeskai, Grixis)
I'm not even sure these should take up 5 archetype slots. Basically, these lists can be divided into UBx (Dimir/Esper/Grixis) and URx (Izzet/Jeskai/Grixis) depending on the dominant secondary colour. The last colour is generally splashed for.
-Dynavolt Control (Grixis, Izzet)
I believe this deck is distinct enough from Counterspell-based control to deserve a special notion.
-Zombies (Orzhov, Dimir (Mono-Black))
Orzhov and Dimir are definitely distinct enough and are not strictly better or worse than the other archetype. It is very possible that mono-Black Zombies is just worse than either deck or than Mono-Black Midrange.
-White-based Aggro (Humans, Exert)
Humans is an umbrella term for 5+ decks, all of which I'm not 100% sure whether they're good enough.
Exert I am unsure about as well; at first I thought it would just not be good; then I came up with a list shortly before Duels was announced to be discontinued; I haven't tested or shared it yet.
-Various aggro decks (Mono-G Stompy, Mono-R Burn, Dimir/Grixis Artifacts)
-Various Midrange decks (Mono-B, Orzhov Tokens, Mardu Walkers, Golgari Delirium)
-Various archetypes I'm unsure about (Ramp (Drazi, Simic, GeistRamp, Grapple), Mill, Simic/Azorius/Bant Tempo, Bant/Abzan/Naya Walkers)