Dude you should be writing in a movie blog. Very good analysis. 

Paul Giamatti have played significant role of campaign manager Tom Duffy in 'Ides of  March'. If it counts as a mainstream cinema. Needless to say  Spacey, Crowe, Washington, Hanks, Clooney, Damon are amongst the best. I will like to add   Michael Douglas, Robert Redford, Morgan Freeman, Forest Whitaker, Jake Gyllenhaal, Joaquin Phoenix, Clive Owen, Ralph Finnes to the list. And the list goes on.

I wonder why you don't like Christian Bale, I think you have not seen 'Fighter' ‘The Machinist’ yet. For Ryan Goslin see 'All Good Things'/ 'Drive' No one can do it better than him I bet you. Actress; Meryl Streep, Susan Sarandon, Diane Keaton, Meg Ryan, Sandra Bullock, Charlize Theron, Britney Murphy, Jodie Foster, Reese Witherspoon, Keira Knightley, Kate Winslate tops my list. 

In the context of bollywood Dev Anand, Guru Dutta, Rehaman, Sanjeev Kumar, Raj Kumar, Dilip Kumar, Rajesh Khanna, Pran, Jeevan, Rishi Kapoor, Anil Kapoor, Amitabh Bachhan, Amol Palekar, Utpal Dutta, Nasiruddin Shan, Om Puri, Amzad Khan, Omrish Puri,  Waheda Rahman, Sabana Azmi, Smita patil, Nargis, Sharmila Tagore are my all time best. 

Nepali haven’t seen much movies. I remember watching Rajesh Hamal’s Deuta and I enjoyed it.