First of all I would like to tell you all that I'm also BIG fan of Rajni.
I heard the album for more than 10 times.
Here is my fav list.
1) Athiradee -- I think some tracks from "new" movie as well
2)Vaaji Vaaji -- Hariharan, Madhushree , Chorus -- I didnt like Gal voice here.. This song like "Indiyan" song "Telephone mani " pol
3)Balleilakka - Kaaveri Aarum - I liked only Chorus voice very much .. First part .. Really too good. Balleilakka means what ? ..
4) Sahara Pookal - Vijay Yesudas,Gomathi Sree,Chorus -- Here .. the tiruvembavai reminded me something similar to "BABA" one song..
5) Sahana Charal -- Udit Narayanan , Chinmayi -- Should have opted for some tamil singer and my fav. singer -- Shreya goshal here.
6) Oru Koodai Sunlight - I think something similar to "Remo" song in anniyan these people might have tried for this .. Lets wait and see , until this will be last in my list.