Lets get some things straight....
All 3 are huge upgrades for Montreal at C. You have a 3C playing as a 1C.
Little is the closest in value but all 3 are no's. It would need to be Little + another roster player wotg value.
Now lets get a few other things out there. We will go off the last 2 seasons:
We will go straight for production since that is Patches game
Patches- G/GP: 0.39 A/GP: 0.40
Average that into 1 82 game season:
32 goals, 33 assists..... 65 points
Little- G/GP: 0.32 A/GP: 0.44
Averaged into 1 82 game season
26 goals, 36 assists..... 62 points
Zetterberg- G/GP: 0.18 A/GP: 0.53
Averaged into 1 82 game season
15 goals, 43 assists..... 58 points
Spezza- G/GP: 0.33 A/GP: 0.45
Averaged into 1 82 game seaspn
27 goals, 37 assists..... 64 points
And Duchene for comparism because he is insanely overrated on here:
G/GP: 0.36 A/GP: 0.34
Averaged out into 1 82 game season
29 goals, 28 assists...... 57 points
So Patches is a goal scorer/producer. These guys are just a tad behind him,
And they are all centres. Spezza and Zetterberg are old. Little/Zetterberg are the best 2 way guys.
Little can PK/PP and take tough matchups. Those stats are playing as a 2C and 2PP as well. I think Patches is underrated on here, but lets be real, his value is not that much more then these 4 C's. Age is the big reason. Little/Duchene likely are pretty close in value.