Lahm had a weak year. He's not even the best RB in the world anymore (Alves is currently), let alone a top 10 player. Robben was injured for a large part of the season, so he's out of my top 10 for 2015. James, Aguero, Hazard and Alexis are very close IMO. Only Messi, Ronaldo, Neymar and Suarez are better. Neuer's season was not amazing as well, not Better than De Gea and Buffon this season.
I'd say
Only field players:
1. Messi
2. Ronaldo
3. Neymar
4. Suarez (played 4 months less)
5. Hazard
6. Aguero
7. Sanchez
8. James
9. Busquets
10. Pique
*Modric, Robben, Alaba were injured for the most important part of the season, so they're out.
*5-7 can be put in any order.
Thiago Silva, Thiago, Rakitic, Pogba, Tevez, Fabregas, Isco, Muller, Lewandowski just missed the top.