Neither. Keep the belt and Satrina's (both of which are very nice pieces) and buy Gauntlets of the Kraken. Your gloves are worse than your new belt. Alternatively, if you want some additional threat and don't mind saving badges for a little while longer, you could save up for the "Cat" chest - lots of stam and armor, and a huge amount of expertise for threat.
Since you have two very nice trinkets, the Key should be one of your last purchases in my opinion. The belt would be a decent-sized upgrade but chest and gloves are more important it seems.
Armory critique: everything looks in order except for the professions! Level those babies