Agree. Gutenberg should provide variables, not fixed values. (Sidenote, paddings & margins should never use "px" unit. Rem is better for scaling padding & margins with typography settings from browsers.) If a system of named selectors is used, I hope it's not the usual scale of sm, md, lg, and xl, which is a short range requiring big jumps between levels.

Something like the Tailwind system is more flexible and future-proofed. Every four levels represent 1 rem and you're able to set the original rem value to whatever you like.

Gutenberg will eventually become a page builder. Momentum of small stuff like this will carry it there. I hope Gutenberg team will look to best practices in the last 5 years of theme development and dnd page builders rather than continuing to blaze their own path. Simply build on top of best practices. It'll make your life so much easier.

On the flip side, Gutenberg is a knock off of Square Space and Medium, which is frustrating to witness. It's definitely not what I mean by building on top of best practices. This reminds me of Tumblr and when WordPress post formats were a thing. SMH. WordPress can do so much better if it would just be itself—cue Mitch Hedberge's joke about hating turkeys.

If you're going to steal from Square Space, steal the entire thing because small differences and butterfly effect will lead to mediocre results. For example, Square Space icon style, sizing, and spacing are a lot more well designed. We can't just take Square Space interface and slap another set of icons on it.