Ten Hag may have tactics and player formations that he can rely on so we won't really know who he will play before the match starts.
Actually what you say makes sense and could provide opportunities for Manchester United but I not sure Ten Hag will use them as you have said.
Both the coach and his players have been very poor with their decision making and i believe that's why they've been less successful this season, their are some matches they lost this season which were the coaches fault due to his wrong choice of player positioning or late/ wrong substitutions, however they had injury crisis that kept many of their key players are from playing but currently most of their players are back in the starting 11 so there should be no excuse of losing today against Galatasaray.
I just hope Eric Ten Hag pairs Amrabat at the midfield area with Casemiro instead of playing him at the left wing area, maybe he could rest Rashford and start Gernacho to be delivering passes to Højlund and play Mount or Pellistri from the ring wing area.