One also could use the Icy Prism instead of PoWar for 8% to dodge
THIS POST has some good info about the second stats. It is helpful to understand how each of the heroic stats give you stuff, so you can make the very personal choice of which heroic stat to go with.
If you mouse over your heroic MODS you will see where you "rank" out of the max ceiling for those mods, and when you get your next point in that mod
This is my Group Warrior - stacking mainly HDex
Mousing over the Heroic Mods you can what additional benefit i get for each of the different HStats (keep in mind these ceilings are based on 4,000 Hstat, so likely impossible to get)
Since there are diminishing returns on how you get mod points from the hstats, sometimes it might be worth getting a little bit more in another hstat than pushing your primary one (that's why many folks use a Weighted chart for their gear)
I get 1 more point of accuracy at 1882 heroic dex (current at 1874 when i took this screenie, so 8 hdex gets me 1 more accuracy)
I'm getting closer to that cap with Combat Effects, so it is going to take many more HDex points to get the next point of CE (CE is trigger procs like on weapons)
We all have our reasons why we prefer different HStats - and unless you're picking HCHA, you'll be fine
For me, since I don't currently raid, and I don't have a tank-dying-problem (and even if i did, I would still stack as much hdex as i could get away with --- dps junkie lol --- I go HDex so I can do more damage and help kill the mob faster, and since i've built my group around melee damage and HDex, I can farm the same camp for augs for everyone outside of my cleric, but HAgi or HSta would work fine as well.
Good luck!