I disagree about Murray. He's got a very low conversion rate. A more clinical finisher could add 8 or 10 goals a season to Murray's haul from the same number of chances. I'm not saying Keatings is that clinical finisher but he's unlikely to be any worse than Murray. Transfermarkt would seem to agree, showing Murray at 213K and Keatings at 234K. Despite Murray having twice as many goals last season, they both have the same goals-per-minute-played stats. Does Keatings keep getting subbed?
I don't know much about Scobbie but, again, Tansfermarkt shows him as being worth 298K to Dixon's 276K. BTW Scobbie's a central defender while Dixon's a left-back.
I'll give you Andreu against King but again we're not comparing like with like - Tony's a central midfielder and King's a right-winger. Mmmmm, donuts... winger.