Guild Wars 2

I have a lvl15 Charr Warrior that has sat unused for a couple of weeks. Partly because low-level Warriors are mind-numbingly easy (I got bored), but partly because I could not decide how I wanted to build going forward.

I want to build a support-oriented Warrior. Tactics seems the key trait line, and it seems I should use either Shouts or Banners. This is my first issue. Both seem excellent, so I cannot pick between them. What are their relative pros and cons? If two Banner Warriors walk into a tavern, do their benefits stack?

My second issue is weapon choice. Again, the class is spoilt for choice and I cannot decide. [Main Hand]/Warhorn seems an obvious pick, so long as you do not go Shouts (Trait conflict), but I am not 100% convinced on this option. [Main Hand]/Shield is another that seems a good choice, but Shield seems more situational. At higher level, would Shield come into its own? For Main Hand, I like Axes, but Mace looks like it would be better for support —- how do they each balance in group and solo situations? The other choice that jumps to me is Warhammer, because the control it offers seems like it would be excellent in both solo and group situations. For weapon swap, I was thinking Rifle. I figure a ranged weapon is essential for the swap, and prefer Rifle to Longbow.

What advice would experienced Warriors offer for the direction I want to go?