Hi Vlad, it's a big goal to keep MoI simple and uncluttered, and so I'm sorry but it's not too likely to get these particular functions built in.

But you can use existing functionality to set them up now - for example if you set up a gridwork of line objects arranged in Golden ratio sections like you want, you can then use the Edit > Lock function to lock those lines so they will not be selectable but remain snappable and you can then use them for reference.

For Russian fathoms units, I'd recommend just leaving the unit system set to the generic "No unit system" and then just consider the units to be whatever you wish.

Thanks, - Michael