To have a QB like Eli Manning is an absolute gift to s GM. The biggest calls any GM needs to make is finding a franchise QB and head coach.
He inherited Coughlin, who is likely headed to Canton. Reese neglected core team needs for so long it cost Coughlin his job.
He inherited Eli Manning, who will go down in franchise history as their best QB, and also may be in Canton. During his tenure, the best Reese could do to protect him was Justin Pugh. Eli has no running game, and can't set up a deep pass without putting his life in jeopardy.
Reese saved his ass by breaking the vault signing free agents that other GMs had drafted.
In a couple years, Eli will be retired, Beckham will command a price tag the Giants might not match, and those high priced free agents will be aging out.
As bad as this year has been, it could very well get worse.