Matthews is the better player overall right now, but i think Stutzle will be in the same conversation by the time he is Matthews' age. Biggest difference here is one is signed for the next 8 years as a highway-robbery price of $8.35M - Matthews makes $11.6 next year with a full NMC kicking in on July 1 (so no guarantees you get anything in return for him if he doesn't want to stay), and will be looking for over $13M next summer. Even if Matthews is still clearly the better player in 2-3 years, he won't be good enough to justify the $4-5M extra per year. He would have to put up at least 15-20 more goals to make it close.
This year is clearly an off year for Matthews, I have him as a consistent 45-60 goal scorer, with 40-55 assists (85 points in a down year, 115 points in a great year).
Tim is probably going to be 35-50 goals, with like 45-60 assists. So also a point per game guy in a down year, but a lower ceiling with the goals.
The answer is Timmy.