He's not worth much / anything at this point or at the roster deadline -- there will be a decent quantity of players like him available on waivers, and with almost half the league presently over the cap, whether it's a good idea to spend $1.25m on him will be a consideration.
That being said, I believe the Leafs do like him, and like having the versatility he brings. He's not as good as Kerfoot in a 3rd line C role, but can play there if Kerfoot ends up on the wing. He's probably not as good as Kampf in a 4th line C role, but can play there in case of injury. If they can find a way to keep him as a 13th forward, I suspect they will.
That being said, the Leafs are in somewhat of a precarious position with respect to the cap. They have a 21-man roster, with $80k in space. Even if they drop Engvall in favour of somebody like Brooks, Gabriel, Robertson, Ho-Sang or Gusev, it doesn't open up enough space to carry a 22-man roster.... so really, what's the point?
I believe Brooks, Gabriel, Robertson can all be recalled from the Marlies under the Roster Emergency Exemption.If signed, I'd imagine Ho-Sang would as well... and the way the Leafs operate, even if one of those guys "wins" a spot over Engvall, they'll value having injury depth over meritocracy.
To me, the only real x-factor is Gusev, as I'd imagine it's NHL or Russia for him. If he makes the team, barring an injury to somebody else, they'll have to risk dropping Engvall.