This is fine.

Also, #287 mentioned ridable entity, so this could be an important feature, and #557 mentioned minecart, which might be possible and more realizable if the whole entity moving control system is rewritten.

Issue #287 for context:

Ridable entities:
Simply put, have a mob saddle, tame certain entities with certain items (wheat for cows/sheep, carrots for pigs), once tamed, the player just uses the use key while holding the saddle on the entity to ride it. (For logistics, it would be easier just to have the saddle texture just be a layer to save time on texture making)

And a refined version:

• Make all passive quadrupedal entities support the saddle
• Animals MUST tamed with their requisite food item before the saddle item can work on them. Message should pop up in chat with "This animal must be tamed to ride them"
• Saddle should exist as a separate texture that should be overlaid upon entities, rather than increase the number of unique frames a texture pack developer needs to make.
• Different entities could provide different bonuses for riding:
  Cows: Can carry items
  Sheep: Move faster on rocky terrain (in reference to mountain goats), or portable bed
  Pigs: TBD
  Horses (when added): Increased general speed. Should not be greater than electric locomotives, as to not harm viability for issue Logic circuits/control circuit system #694

Thanks for organizing. And for ridable mobs, they would require some biological needs, so may differ more from machines.

Thanks for organizing. And for ridable mobs, they would require some biological needs, so may differ more from machines.

Just, make sure to balance it, we don't want to make horses OP, or too inconvenient to maintain.