my experience was like the same, but for me as theme developer the “lazy blocks”(https://wordpress.org/plugins/lazy-blocks/) plugin added a backend interface for creating blocks with individual output templates and possibility to disable container markup at all (which was my main concern)

i ended up exporting stuff that work with my self-developed theme and now i am absolutely fine AND happy with Gutenberg.

Your post outlines for me what i think i have to learn the next Months 😉