The issue is that bricks like this lose utility when they are attached to a brick. Instead of being able to use wall bricks in any manner, attaching them to any kind of wall surface, you would now be limited to the brick shape connected to it. Also, reworking bricks to accommodate for your preference is kind of a reach.
At this point the best workaround is either a floating bricks mod
(which I already knew you dismissed), placing/deleting bricks with the new duplicator with either /cut or /tfp
(which I know you called tedious), or the brick that Shift Kitty posted
(which wont work within zones).
Floating brick mods is the best option since it removes the need for any supporting bricks. It can be made admin or superadmin only through preferences if you dont want random players placing floating bricks everywhere. Im also not sure why you would need to use /clearfloatingbricks if you are the only one building and if the Floating brick mod AND the New Duplicator have preferences to lock floating bricks to admin+ only.
To make the brick floating which exposes it to /clearfloatingbricks, exposes it to hammer/wand effects and exposes it to accidental CTRL-z which will break ALL CONNECTING FLOATING BRICKS.
Also, these issues were fixed. Check it out:
https://forum.blockland.us/index.php?topic=316793.0There are 0 reason to not use Floating Bricks at this point.