There really is no 'correct' way to build your brute. Slotting for nrg defense can be very effective if you plan on hunting rikti, or a general build would just go for regen/recharge. Personally, I'd go for regen/recharge.
To begin with, there are many different paths you can choose to go on a WP brute.
-You could go for elemental defense sets, so you'd be looking at ST sets like 3-slotting part of it with Pounding Slugfest.
-You could go for recharge, which would be 5 slotting with crushing impact.
-You could go for regen, which would be a mixture of a lot of different sets.
-You could frankenslot for a cheap build.
QR
On my SS/WP I built for +HP and then slotted for max damage. I have a seamless attack chain right now and wasn't worried about getting more recharge. I use Gloom from GW's PP to fill the gaps I had prior to level 41.
But has a Mace/ Brute, using Gloom would cause re-draw and that might be an issue for some. In other words, you might be able to build for +recharge/+HP to get a better attack chain without resorting to Pool attacks, and for a weapon set, I think that's a good goal.
To Tonal,
If you use Mid's take alook at building for +HP over +regen. While regen is nice for /WP, additional HP would increase your regen and survivability better. And most IO sets that offer a +HP bonus will offer a +regen component as well.
Just food for thought.
Yeah, I haven't seen many threads dealing specifically with IO's either. My WM/SD brute is 36 right now and I just started doing the IO's. i have a couple complete sets of Crushing Impact and I think scirocco's dervish in a couple PbAOE powers as well.
My issue was I never really understood how it they worked. When I saw the bonuses of 1.5% Def or Reisitance or whatever I thought it increased by that (i.e. a base of 15% would go to 15.23% (15 x 1.015) rather than how it really works (15 + 1.5 = 16.5%). Pretty big difference. I wish I realized this earlier 
Good Lord, it is expensive though
Try my AE Arc: Out of Place, Out of Time ID#304340.
Leave your Arc title in the feedback and I will check yours out as well.
What IO sets would be good for a war mace / willpower brute? Surprised none of these sets are stickied.