Summoner is capable of getting good to great bayld gain in reive's currently ONLY if they are spamming healing bloodpacts every 45 seconds and ONLY if those heals are all healing for close to their full potential. Is this unbalanced? Potentially. Is nerfing this going to fix any problems? No.

Why you ask? Well for one, this would screw over the summoner massively. If you try a summoner and go through a reive only throwing buffs / debuffs every 45 seconds (we are assuming an offensive BP on CD on roots or a mob every 45 in either situation) you are going to make trash bayld. There is little to not bayld gain for anything but doing effective healing for a summoner, which is why you see them doing it. They are forced to for ANY bayld gain.

Secondly, you would probably screw over reive's in their current state. A lot of the time the only way everyone is getting enough heals in basaalt fields when two turtles end up spinning on top of each other near the whole group, is if summoners are getting heals off. Lets face it, targeting in this game is archaic at best, and when you put 40 people in a tight space, not everyone is going to have a party, and as a healer you aren't going to bother trying to heal the people not in your party. People are going to die. No one is going to be happy.

Basically what I'm saying is you haven't offered a decent solution. Colonization reive's aren't Odin2 or Legion. They don't seem to be designed with the idea of being forced to put together an organized group, though you certainly can. Saying summoner would be fine if you changed reive's to be like those events is wrong. I don't get the option of targeting my heals / buffs on another party / group. Sucks, but that is how it is.

Finally for an example of how bad bayld gain is, doing a nakuul the other day (yay plenty of bayld to do nakuuls which drop no summoner gear because there is no summoner gear to spend bayld on) keeping up pet buffs / debuffs in a rotation on a large group of people and using off BP's, I made about 8k bayld over the course of the hourish long fight. My dps friend made closer to 20k (keep in mind for the last 20% I went back to healing / status removal to get up to the 8k). If I had been healing the entire time instead of attempting to contribute useful buffs / debuffs, I would have been closer to the 20-25k people are reporting are possible.

TLDR: tried to do useful job things my job seems designed to do, got screwed on bayld. Nerfing the one useful thing I can do to get bayld not the solution to the problem you are having.