Just to get the full redstone experience, gravity blocks can be used in circuits as a pulse shortener. Slime blocks would allow us to make movable tiny structures.

Thanks for the suggestions! Both of these ideas have been in the back of my head for a while. They may be a challenge to implement, so I don't have an eta, but they are definitely on my list of priorities.

oh, also target blocks have unique properties

• Slime blocks
• gravity blocks
• target blocks (maybe)

I'll consider target blocks. It would be a very small target, and since there's no tiny dispenser, it may not be useful for automation. I'm not sure how useful it would be.
Edit: Also, since you can already choose the direction of tiny redstone dust connections, the fact that vanilla target blocks force redstone connections is not relevant in Tiny Redstone.

Yeah, choosing the direction of Redstone kinda negates target blocks. I forgot about that.

Don't forget tiny honey blocks to go with the tiny slime blocks!

Speaking of, has anyone tried making tiny flying Redstone machines yet?