Whereas I would agree that filling the position of RB was key, I wonder whether NH signing someone like Gunter would be sending out the wrong message about how he wanted to take us forward, that is to say someone ageing.
No doubt he would be having dog's abuse, not just on here, if we had signed him and performed the same way as we have to date.
Plenty going on behind the scenes we don't know about, the Big Three aren't exactly transparent about anything and as has already been mentioned on here, the main problem lies up the top and the long term plan, or lack of.
Edit:
Re the OP, midfield is definitely a problem and two of any of the aforementioned four I'm afraid just aren't up to it.