Quite a lot wrong with this so thought i'd break it down.
Nobody on the forum knows what position Pep views him in. Not sure of the relevance. However, I will offer some direct quotes as to where Pep sees him, just on the off chance that's more valid than your perception of what Pep thinks. "He can play in all three positions in attack, he has lots of energy, defensive intensity, one-on-ones, dribbles, with a vertical sense of the game, and he is also a great kid." Also, "I think the position Arsenal are using him as a striker, in front, it is perfect for him,"
David Silva is playing a free 8 role. Alexis Sanchez isn't playing anywhere near a free 8 role.
I don't think the club would sanction a £60m bid for a 'short term move'. Again, this is completely opinion trying to be diagnosed as fact/justification.
There is plenty of football logic behind it, the same logic that meant we wanted to buy him all summer hasn't changed just because the window is closed and we're playing well. Pep sanctioned his sale at Barca so I don't think 'mis-placed' loyalty came into it back then, and it won't now. He wants him because he's versatile, understand's Pep system and is a very good player at a very good price.
Apart from all that, good post.