This are the conditions to how the fight would take place, it is a 1 vs 1 fight, fully rested haven't fought any one, perfectly healthy at their prime, no Edo version(i.e. so if you pick Madara he won't have the 1st DNA), the terrain will be suited 50, 50 for who ever you pick so none of them has a greater advantage to the other because of it and the distance that they will begin fight at will be the distance that the fights started off as in the chuunin exams. Cant wait to see what you guys pick. 
My would be:
Shikamaru vs Neji
Sarutobi vs Jiraiya
Shino Vs sai
Itachi vs Sasori
My would be:
Shikamaru vs Neji
Sarutobi vs Jiraiya
Shino Vs sai
Itachi vs Sasori