My view on him remains unchanged from last season - Mata is very aesthetically pleasing both on and off the pitch, but he doesn't actually offer a huge amount in terms of penetration and creativity. He is for me, a luxury player whose strongest attributes are his technique and finishing. As a playmaker, he simply does not do a great deal outside of the opponents penalty box. He doesn't dribble and take players on, he doesn't play defence splitting passes, his work rate is nothing special nor is his defensive contribution.
It's the same as last season where we looked completely devoid of creativity, and whilst the caf was only too happy to heap the blame on Young and Fellaini, we offered nothing from the right flank. We went 3 games without scoring and yet Mata was always absolved of any sort of blame. For his role in the team he should have been and should still be one of our primary playmakers, and I just don't see him doing that, compared to others like Silva, Coutinho, Cazorla, Fabregas etc...
Having said all that, I can see a place for him along with Rooney and Memphis in a fluid front three, provided we sort our midfield shape out rather than having two defensive midfielders and a #10 who basically operates as a second striker.
If it had been me however, I would have loved to see Nani and Memphis as our wide men in a proper 4-3-3.