You might well be right. I am trying to be objective in terms of what they did productively. I remember Milner scoring a fair few goals and if memory serves correctly a good percentage of winners in tight games. He did play quite advanced for Villa and I guess he is some competition up there for City. However I have never seen an engine like him on any other player, he was literally box to box when required, would be up there with every counter yet back defending or tracking runners. It felt like we had 12 players when he was playing. Seemed good at being in space especially near the end of games when markers were tiring. He was decent at crossing also, he could appear on the pitch in any place. Loved his attitude.
Delph doesn't really score many, make assists, or great at tackling (bad tackles is a strong suit) quite small so doesn't win many headers. He is a bit like Cleverly in those terms. Both liking to keep the ball moving, short accurate passes good off the ball in making himself available, Delph though is a good dribbler off both feet, likes to turn and drive (can be a weak point when he keeps doing it int trouble). Incisive passing is not a strong point he certainly won't be threading balls through unless that is something he has been hiding, or Villa are bad at playing on the shoulder. He has loads of energy, works hard, happy to close down and although a reckless tackler (used to be really bad but think he improved last season) can work well in a defensive unit. It might be that those aspects of his game suit City. He might get more space playing for City, however I can't see him getting as far up the field.
He is definately not better than Yaya by a stretch apart from attitude and desire, and I've not noticed enough of fernandinho to comment.
Quick decisions, you must be having a laugh!