For me the most important signing would be an amazing goalie. Remember when we had Nev and later Nigel Martyn. Brian Clough signed Peter Shilton for a record fee if I recall properly as he felt a great keeper was worth 20 points , games won that would be drawn and games drawn that would be lost otherwise. How many times in the last few years have we suffered from bad goalkeeping. Look at the very top teams and their keepers, De Gea, Courtois, Loris, even Hart Euros, withstanding . They are as valuable and maybe more than anybody else. They rarely gey injured and play at the top of their game until mid to late 30s. Look at Arsenal and our neighbours how they've also suffered recently with suspect keepers.