Thank you. I hope to see more anecdotes like yours. There is no need to apologize for using metric references.
I also include a sheet size in my title blocks. Here in the US it's usually one of the ANSI sizes (A, B, C...) instead of the ISO sizes (A4, A3, A2...) since those are the common printer paper sizes sold here. I usually draw schematics on ANSI B size sheets (often called "Ledger" or "Tabloid"), which are similar to ISO A3 size. 99% of printers here print on ANSI A size, usually just called "Letter", and similar to ISO A4. Inkjet and laser printers which can handle the larger B size aren't too expensive or uncommon. I avoid using larger sizes like ANSI C or ISO A2. We have large format inkjet printers at work which can print them, but I find the larger sizes to be cumbersome in the post-drafting-table era.
A last-modified field is a good idea, especially for changes in between releases. I plan to include a similar field, as well as a git revision field. I still have to decide how I will handle the revision field in the main title block. I think the manufacturing folks at my company like to see letter revisions like "A" or "B", but I like to distinguish between PCB layout revisions vs. component value changes on the same PCB layout. I've previously used a dotted numeric convention like X.Y, where X is the PCB layout version and Y is the BOM revision. But I don't think that would be accepted as well in my new job.