This for me as well.
Anyone questioning the Sabres depth & overall quality at forward has me questioning their own sanity.
Even if Vesey doesn't sign (I still feel people are making too big a deal about hm but will happily be proven wrong) the team is stacked up front.
The 'D' on the other hand... And some people are OK with this - again very questionable.
I don't know if stacked is the right word. I would say they are on par with the other playoff teams in the east. Pittsburgh, Washington, and Tampa all have much more proven depth. There is also a decent chance that Kane doesn't play another game in a Sabre uniform, which could move the needle in the other direction.
I'd rate a fully healthy sabres squad as above average in forward depth. If Eichel puts up 80 points and Reinhart puts up 50 and Girgenson's has a strong rebound year, things could obviously tick into the excellent category.
I'd rate the D similar to you, average to below average with a pretty average prospect group on D. There's an obvious immediate need ( top pairing LHD) and long term need.