Best team under cap? Eh, I've seen better.

It's still a very good team, though, and I could see them going pretty far if all goes right and Vasy stands on his head. Not a cup berth though, conference finals at best imo.

The biggest weaknesses are the RW depth (why is Caufield on the second line) and the defense. The first pairing is good, though it would help the depth if they were split and there was a more offensive-minded defenseman paired with each. Also, the fact that not a single pairing has both defensemen on their strong side is... a little comical.

between matthews, tkachuck, vasilevskiy and petro there is about 40 mill combined you could have way better depth if not spending so much on them same with dvorak better 3C options for cheaper

instead of vasi shoulda went sheshtorkin, gibson, markstrom, helle idk multiple different options that aren't far behind in skill but much cheaper.
tkachuck replace with barzal, bergy again so many better options for cheaper

as for matthews if you are gonna spend upwards of 11mill might as well get mcdavid
if not save yourself 3+ mill and get draisaitl instead