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Hi @logaritym,
Thank you for the suggestion and for testing multiple blocks and sharing what was the one that worked best for you. Your tests may be useful for people with a similar need.
Including blocks in the core has a significant impact, e.g., the bock code is loaded for everyone; even if that site does not use the block, there is also a maintenance impact given that the blocks need to be maintained for a long time (maybe forever). So core provides a fundamental set of blocks that are probably used by more than 90% of the users, but thanks to plugins, users can take advantage of other blocks the community build.