It's been a while since he has settled for the 4-3-3 actually..
With Di Maria as a midfielder and Bale or Jese on the right..
The roles are the following in my opinion:
Gk (defend), 2 CDs (defend), Marcelo is a complete wing back on the left and Carvajal an attacking fullback on the right..
Alonso i'd say plays as half back at dmc, with Di Maria and Modric ahead of him as Central Mid (support) and DLP (support)..
Ronaldo and Bale are inverted attacking inside forwards and finally Benzema probably plays as F9 or DLF because he drops deep..
Generally they try to hold the ball and control games, and without it they press a lot till they get it back..
Defensive line is preety high and the tempo i'd say depends on the game and the opponent..
With these players though, i'd say that the team lacks creativity, so i'd swap Di Maria for Isco and play him as a Central Mid (attack)..
Ancelotti generally prefers Di Maria because he's a lot better defensively..
Try it and i hope it works..