This is such a hard one for me. I'm taking into account who we still talk about from the past the most, and who from recent times will we still be talking about, our kids will be talking about and so forth. My list:
Largent
Jones
Wilson
Lynch
Largent and Jones go without saying. 2 of the best at their positions to ever play the game. Wilson, this is a hard pick for me because I definitely don't like the guy, and I think his downfall has been karma for him. However, there's just no denying what he did in Seattle, period. Lynch, I believe he really set the tone for the LOB days. But wait, Lynch is a RB, how can he be part of the LOB? Because Lynch brought the BOOM that fed the Legion. He set the tone for the whole team, he was the spark that set it all off in the first place and the spark throughout his time here in Seattle.