Building user experiences is inherently some of the most difficult software engineering there is.

It's not difficult because the existing tools are poorly made (though most of them are), it's difficult because the core problem is extremely complex (in the Rich Hickey [1] sense of the word, e.g., braided, intertwined, complected, etc.).

In order to build a user experience, we start with some information that can often (though certainly not always) appear both simple and easy (i.e., unbraided and comprehensible). But then we must create a projection of that information onto a 2D (or 3D) plane and manage it's changing state over time.

This is where everything falls apart. We're usually trying to manage a very wide, very deep, loosely defined tree of state and we're trying to reflect an arbitrary number of user interactions and mutations instantly, and over time.

Exactly zero of our tools (programming languages, UI toolkits, Operating Systems, etc.) have strong support for managing change-over-time in a way that makes this type of problem fast, stable or enjoyable to present, use, verify or mutate.

I love that the OP showed the triangle of Performance, Adaptability and Velocity. I've been framing a similar concept with teams since 2011 which I refer to as, "Fast, Stable and Delightful."

It's my thesis that we need to balance these three requirements in both our activities and in the output that we produce. This balance is incredibly difficult to achieve and harder still to maintain.

Different organizations tend to focus internal power in one of these 3 nodes (e.g., Google on Stable, Facebook on Moving Fast, and Apple on Delight). Note that the desire to move "Fast," or even to be "Stable" rarely achieves the desired result.

The only organization I've seen manage these values effectively is Apple and I believe this is because people there have understood for decades that speed and stability are prerequisites for delight, but that neither speed, nor stability (alone or together) are sufficient to make something that gives humans the sense that someone, somewhere actually cares about how they feel.

I love how the OP is exploring this problem space and how they are digging into the existing solutions and trying to define the problem with some rigor. This is fertile ground for exploring new ideas and new approaches. Please do not discourage this activity!

[1] Simple Made Easy: https://www.youtube.com/watch?v=SxdOUGdseq4