I wonder if this interesting new situation - blocks and layout - should not also merit consequences for the way Kirby is treating permissions.
As yet, in websites where I am not using blocks and layouts, Kirby is a CMS where I as the developer very strongly pre-structure the panel (and therefore the possible contents of the page) through the use of blueprints.
Simply put, I decide which of the contents of the page are at all editable for the users, in the panel. And normally, users can change neither the properties of the elements (e.g. textarea) I am giving them nor their order. This applies even to users with admin permissions.
In fact, on a site without blocks, the only way they can somehow effect a change to the elements of a page and their order is by changing the template of the page, as a whole. And this can be handled by simply not giving them the user permissions necessary (i.e. changeTemplate: false). The permissions here are not on the field or subfield level, so Kirby allows me to do this.
However, with blocks and layouts, the situation is changed. Blocks allow users to change the whole structure the page. Of course, users still cannot edit the block’s code. Yet they can easily swap one block for another and change their order and layout on the page.
In a way, I see, of course, that this is the whole point of blocks. It is what is so great about them.
However, I wonder, if these kinds of big decisive changes the users can now make still belong to the category of ‘field or subfield level’ permissions which are not possible in Kirby - of if they should perhaps belong to a more important category of user permissions similar to changeTemplate?
In my view, it is one of the big strengths of Kirby, that I can build a custom panel where users can only do what they are supposed to do - and are never confronted with unnecessary menus or options. This is actually what many of my clients like about Kirby. And, for me, it would be really great to be able to do this, to keep things simple in the panel, even when I decide for some reason to use blocks.