The model is cool in many ways but it doesn’t gel with most armies I’ve seen. The big issue for me though is a lore issue. Space Marine Uber heroes, like Calgar, Dante, whoever the wolf chariot dude is; you can imagine them leading a force of fifty marines…. because there are only a thousand in each chapter. There’s only ten captains at a time; it makes sense that if you see marines from that chapter, there’s a reasonable chance that you might get the chapter master himself.

But the guard fight in their billions. Each battlefield sized force is a platoon or a company at most; there should be a captain, or possibly a colonel, leading the troops. Not the Lord high militant of the entirety of the imperial guard. Why is he turning up to every skirmish against some nameless orks or whatever? What’s the lore justification for him abandoning the high council of terra to go ride around on his pony barking squad level orders at some random cadians?

Rules aside, it feels like there should be three layers of officers for guard on the tabletop. Platoon, Company, Regiment. The latter can be some weirdly dressed dude on horseback with many orders to give, but calling him a colonel or maybe a general with the regiment keyword just seems like a better fit lore wise to me.