Think Appleyard is a bit optimistic.
Giroux is 1LW right now, but I won't give him more than a year or two left at that level, he's 32 this year.
Voracek is a 2RW, first line scorer, but bad defense lowers his value. He turns 30, not sure he can adjust as he loses speed.
JVR on the other hand, with the right center should play better this season, he was more reliable in Toronto with Bozak.
Hayes is a pretty consistent 5x5 scorer: ES 39, 30, 35, 34, 41, that's borderline 2nd line production.
Compare to Voracek the last five years: ES 48, 32, 38, 50, 48 - average 43 v 36 for Hayes.
Figure maybe a couple years flirting with 40+ ES points, then 30-35 the rest of his contract, solid 3rd line production.
So while he's going to get overpaid, it's not going to be a gross overpay, back years he should still be a $4-5M value.
The real key is whether his defensive improvement is sustainable, as a plus defender he's worth a bit more.
Patrick and Frost, if they play up to their talent, won't be blocked by anyone, since in that case they're in the top 5 among our forwards.
But at age 21 and 20, when may be a more pertinent question than "if."