This isn't going to be fair to Gilmour. It's Trottier for sure. He would be a top 30 player of all time and that's being a little liberal about it too. He won 6 Cups, was a huge part in 4 of them and won the Hart Trophy. Not to mention he has two first team all-stars and two second team all-stars while Gilmour has none.
Oh and he's a HHOFer while Gilmour is not, although like many of us I believe Gilmour is a notable omission in the Hall.
But let's break it down. Trottier wins on offense, defense, goal scoring, championships, physical play and leadership. Gilmour I would say was the better playmaker. Not bad, but Trottier gets compared to other centers like Clarke, Yzerman and Sakic. Gilmour is more along the lines of Oates.