But what if I want some doctrinal mobile AT as okw to fight off light vehicles? Do I pay an extra 300mp to get a 2nd sturmpio squad to get a sweeper? Why do all that when you can bundle them together and get both a sweeper and an AT.
I don't really get your point. I personally almost never get a Panzerschreck on my Sturmpioneers so I certainly wouldn't ever want to pay 90 munitions just to get a minesweeper (your bundle idea) and even lose a significant portion of the AI power of the unit along with it. I do not see how that would be an improvement.
To allow them to upgrade to both simultaneously (one upgrade no longer locking out the other) seems fine and a nice QoL upgrade to me, but turning it into a bundle certainly doesn't.