That was fun to read. I don't think anyone can tell if it's realistic, but it was well thought out enough to enjoy
Lines wise, I wouldn't scratch Byron at all. Since his return from injury, he's shown exactly why he's valuable to the team and has that "A" on his patch. At the very minimum, you need him on PK. Also, Toffoli probably can be more impactful on the 2nd line than Armia. Here's what I'd propose as alternate lines:
Tatar - Danault - Gallagher
Drouin - Suzuki - Toffoli
Kovalchuck - Kotkaniemi - Byron
Lehkonen - Perreault - Armia
Clifford
Weal
(Evans in AHL, he's the first call-up on the list, or if Perreault falters, he's the replacement)
Keep defense the same.
Obviously I assumed KK is back in shape and more than just a 30pt guy. His camp will tell his story. Still think he could be a better 3C than Perreault.