The impact is only felt by people who operate a certain way using certain habits. I have no 'fear of crashes' carryover from MSTS days so I rarely use the save button and the only time I do is when I need to physically step away from the computer. The location chosen was a hidden folder originally so I don't think the intent of the developers was for everyone to be "going there" all that often. We users develop experience over time however that may contradict the original intent, and sharing solutions like this is what forums are for.
Automated saves, saving just for the hell of it with no real need, that some users are currently lobbying for, adding more file clutter, is one of those things that the current saved activity cache system is not really 'ready for primetime' for.
One minor correction, it is not the CTRL key, but rather the ALT key. The above paragraph should read
Holding [ALT] and punching F5 brings up old Hud. Holding [ALT] and [SHIFT] and punching F5 allows you to page through all the screens of the old hud. Brake info, Loco info, Force info, Dispatcher info, all those usual pages. Holding [ALT] and punching F5 again makes old hud go away.