Gnome, I have re-arranged your list to sort by fewest defeats. More appropriate to current situation as to who is likely to win a tournament perhaps?
Maybe Stan should be on your list? His W/L is 15-2 - not bad!
Looking at this year's results, I see Djoko (2690 points) and Nadal are up to 1 & 2 in the race rankings after Miami, pushing Stan and Fed to 3 & 4. Berdy not far behind on 2045.
Then the next group all very close
6. Dolgopolov 1130
7. Ferrer 1080
8. Nishikori 1025
9. Dimitrov 1015
10. Cilic 1010
11. Murray 1000
12. Fognini 930
Nishi, Andy, Fognini playing DC this weekend would gain 65 points per win in live rubber. So Andy could be back in the top 8, even if only until Monte Carlo.
I think Dolgo must have played every week this year, with 9 tournaments already!
Edit - Nishi not playing DC, still out with injury.