For the GRUB issue, it was probably using the Steam controller as the primary keyboard. Without steam running, the controller works as keyboard and mouse, so you can navigate bios/etc with it. On the GRUB screen, you could have probably selected the boot up option with the controller.
I'm guessing by changing USB ports, you now have your regular keyboard on an "earlier" USB port, so it takes priority over the controller.















It's angled, but it's also narrower than the deck, which can make angled grips more necessary. I've heard both sides, some people say the grip angle is more comfortable than the deck, others say it's not angled enough to make up for how much skinnier it is.