Awakenings, Goodfellas, Silver Linings Playbook, A Bronx Tale, Sleepers (albeit a smaller part, he still does it brilliantly), Casino, Heat, Jackie Brown.
Glengarry Glen Ross, Sent of a Woman, Heat, Any Given Sunday, The Devils Advocate, Insomnia.
Why do you feel that he's been relegated? This isn't right, assuming that because someone plays a supporting role they're less relevant than the lead man, especially in the case of Seymour Hoffman who has done nothing short of brilliant movie on top of brilliant movie, pulling so much weight in his limited screen time.
I just told you what I would like him to do. I'm not sure if I can explain it better, either I'm terrible at explaining or you just won't accept my argument - either way we land at a blind alley