War Mace is great and you can pair it with anything, so it just depends on how you like to play. Some secondaries like Bio are very clicky -- great sets with top-shelf survivability so long as you're clicking the powers that save you. Others are pretty hands-free, like WP and Invul. Some have some endurance built in, but that's less of a problem these days with all the uniques/procs that help with end. Some deal very significant amounts of damage.
So again, it really just boils down to what you like.
WM hits hard, can be distilled down to a great attack chain with fast-animating, hard-hitting attacks, and has two excellent AoEs -- one a pretty tyipcal PBAoE that you'll enjoy, and another targeted "cone" with a crazy awesome 180-degree arc that you'll adore. In my opinion, WM and TW are now the strongest-feeling melee sets in the game. SS is great, but only a couple of its powers really feel super strong. In WM every attack feels like it hits like a truck, and most do. Tons of knockup, so it's also one of the better damage mitigating sets.