It seems using Blocks needs a Pro account.

But so far，I don’t think I need to be a pro.

If you can offer a choice,

just like $2 / 3blocks & $10/20 blocks,

may be I want to try.

and I think the more people buy for blocks, the more will subscribe in the future.

&& developers may also built the 3rd party Blocks,then earn money from the usage of their Blocks。