Each expansion I get hyped and also worried about more skills.

[Ultimatecalibur]

I follow you on that, 1 2 3 can be monotonous on tanks and MCH but that should be extended, not compressed in a single button.
Otherwise you'd get the same result but you'd manage to make it even more boring.

The idea behind compression is that you end up extending things with the room freed up by the compression. You turn 1, 2 and 3 from being a single 3 button combo into 5+ actions including the previous 3 button combo.

For example with MCH you could: Turn the 3 button Split Shot->Slug shot->Clean Shot combo into Split/Slug/Clean shot combo, add a 1 button 2-step branch off Split Shot that extends Automaton deployment time when used with no Battery generation, and add a battery consuming 2 stage Chainsaw attack that works like BLU's Phantom Flurry. 3 buttons turn from 3 actions into 7 actions.

I'm now imagining a poor sprout switching to SAM for the first time and seeing three Hakazes on their hotbar. 11, 122, 133 or whatever would work, of course.

Which is why you set it up differently.

You would have a Hakaze(default)->Yukikaze button, a Jinpu(default)->Gekko button, a Shifu(default)->Kasha button, a Fuga(default)->Mangetsu button and an Oka button.

Pushing Hakaze would turn it into Yukikaze with the combo ring while also putting combo rings around Jinpu and Shifu. Pushing Jinpu or Shifu would turn them into their 3rd step while reverting Yukikaze back to Hakaze.