Ultramatum, I know this post has been here and been quiet for a while, but I was going back through it again and wanted to say thank you for posting this way back when. When I was first building my support guardian well over a year ago, I stumbled across this post, and it became the bedrock of my build. Especially regarding rune-based boon duration and the use of consecrations, this stuff is gold, and to this day, my support guardian is by far my favorite character—and my friends' favorite, because the boon output is like steroids for everyone in the party
The only thing I've done in my build that's notably different from your design here is something I also seldom see other support guardians do: put points into Radiance to get Renewed Justice. It seemed like a no-brainer to me, and I've never been able to get myself to go without it because it has the capacity to totally turn the tide in a fight against large numbers of enemies. Particularly when used in combination with AoE weapons, like hammer and staff, it's magic! Every time an enemy you've tagged falls, Virtue of Justice is re-upped, supplying another dose of might and fire damage to everyone in the party. I've been in fights where I've tagged so many targets that once they start falling, I can't hit VoJ fast enough to keep up with the renewals. Toss in some superior sigils of stamina, and you're hitting your party with dodge-heals on ever kill as well. It's fantastic in big-group fights.
I'd also chime in with the people here who've championed the use of the hammer in place of any one-handed weapon-sets—at least in PvE. I've always loved its steady stream of protection that lets you get up in the enemy's face and add survivability to your frontline teammates better than any healing could. As importantly, though, when you're running with consecrations, the hammer's blast finisher turns them into repeated boon sources, enabling you to throw around area retaliation and might like they're candy. People can say you need to use shouts to really give good boon coverage, but they're wrong. If you understand symbols, consecrations, and combo fields, you can easily feed your party boons without end, on both your hammer and your staff.
Regardless of the couple of things I do differently, your work here is fantastic, and my guardian wouldn't be half as helpful to parties—or half as fun to play!—as he is if I hadn't found this. Thank you!