The bow is underpowered for GvG. very good zvz and OW. The problem is you can't use the Warbow, longbow or Bow of badon for 5v5 due to the inefficiency of those wep for this type of fight.When people say stuf like: "the bow is underpowered" i actually ask myself which one of them? There are quite some types and also quite some builds. Your bow build can be weak, not because of the bow, but because of the rest of your gear... The other way around is also the case, your build can be weak, because of the current meta, that counters it.
There is also a problem with balancing the bow. Kiting is interesting because it is either underpowered or overpowered and there is not much in between. For instance you can hit and run infinite or only finite amounts of time...
Warbow is good for ow but still has too low damage
Longbow and badon is just aoe zvz wep.
Now we just have whisp and standard and those bows are better than all other for GvG but still underpowered. There are couple of build and i have tryed a lot to. Always the same thing, bow is attack based damage with no burst and not very good utility. All other Rdp burst way better and get utility. Yes bow is doing probably the same amount of damage but for a long period for single target. All your damage are usually done during 8 sec or during 7-8 auto attack.
Also, just out of interest, I compared 1H Frost damage with Bow's damage:
Frost Q: 242 damage (25% slow)
Bow Q: 248 damage (15-60% cast speed increase)
Fire Q: 242 damage (plus stacking dot)
Frost E: 459 damage (20% slow)
Bow E: 483 damage (3s root)
Fire E: Wall of Flames, who cares about the damage
I'd say you can 1:1 replace a frost user with a bow user. Only difference is the slows and the E's. Bow actually does more damage than frost in a glass cannon-setting.
Bow isn't underpowered. Its in the exact same boat as all non-meta ranged weapons. As fire is getting nerfed quite frequently, it opens up the playing field for other ranged weapons.