I'm not an experienced healer so I could definitely use some advice but this thread is also just to talk about the plight of healers in BGs.
I thought the Warden set for Endless Archive looked pretty good so I threw it on a PvP healer. I'm using Gardener of Seasons Ice Staff front bar: Crystallized Slab, Deceptive Predator, Polar Wind, Soothing Spores, and the weird grappling vine thing that I've never used before and can't remember the name of. Trees ulti. Rallying Cry backbar sword and shield: blue Betty, ice fortress, Resolving Vigor, living trellis (using the minor lifesteal morph, can't remember name,) and Lotus flower (the one that heals more than one target.)
Things the build has going for it: It's pretty survivable so that's good. Not as incredibly tanky as some healers I'd wager, but I'm wearing the wild hunt ring and I'm using deceptive predator for speed and minor evasion. Couple that with the grappling vine and I'm both able to get out of dodge and stick with who I'm healing very well. I'm stage 3 vampire, blocking on both bars, have about 38k HP, and a fair amount of crit resistance (rallying cry,) plus reduced block cost. So the survivability is like B+ level I think.
Also, if you hadn't already noticed, this is a very high Ulti Gen build. Very high uptime on major and minor heroism. Extra ulti when I use the grappling vine. Extra ulti for activating an animal companion ability (I think that's right?) Extra ulti for using my Ulti on low health targets. I'm running the tree ulti on both bars, and I can drop them... Frequently.
Things I provide my group beyond healing: 250-ish weapon damage and 1300-ish crit resistance. Occasional (working on my uptimes,) minor heroism and/or major cowardice to nearby enemies. Minor toughness. Minor recoveries buff. Oh wait I just remembered I think I'm wearing Magma Incarnate so I'm also helping with minor resolve and minor courage.
Downsides: I don't know if it's a console issue or just a me issue but I'm not really sure when I'm successfully overhealing and when I'm not. If someone needs a fat heal I try to hit them with Polar Wind first and then immediately hit them with spores. I assume it works out most of the time but I'm really not sure.
I don't have ANY damaging skills. So I'm pretty useless without somebody to follow. And I'm finding my teams feel a little, uh, aimless sometimes. A combination of "well I don't do very much damage do I?" And "I don't know or care where I'm supposed to be."
I've had a few capable teammates that I'd follow around helping go on killing sprees but after about 5 minutes of them never doing anything to win the game I'd leave and see if anybody else gave a crap.
Obviously this problem is worse for me specifically because I'm an OBJ noob and all... But seriously, I'm a healer bruh. I'm not getting any killing blows here... Help me WIN. I'm here to help you be awesome. Please help me win, lol. Being awesome while losing perhaps hits even on the joy-o-meter but helping someone else be awesome while losing registers 0 joy, I say again, 0 joy.