The most important factor to take note of when making new signings isn't necessarily the stats your targets are rocking, but the role they can fulfil within your team. This is the first thing you should establish before tabling a bid.
Players whose natural play style will force you to overhaul your tactics are a no-go. For instance, there's no point chasing wing-backs if you usually play a flat back four.
Cold stats, of course, do come into this. If you're getting results from fast, counter-attacking football, throwing a new signing who has a meagre six for pace into the mix is only going to slam the brakes on the momentum.
Similarly, if hoisting the ball forward and bombarding the penalty area with crosses is working for you, signing a forward with 16-plus for heading would be wise.
The most important thing to keep in mind when looking over those numbers, though, is how the physical attributes they represent will tie in with your style of play.