BOV is quite bad, providing up to 5 players with a 35% beacon whereas BOF constantly provides two people with 35% beacon.
Once it is understood that the beacon transfer strength of BOF and BOV are the same, we can begin to think through this.
In the context of M+, where BOF used to shine, it only proivdes 4 players with a beacon. The reason for this is when only 5 players are present and all 5 have beacon, then only 4 can possibly benefit because you are healing the 5th (who will not get the beacon benefit). We will not consider a scenario where you’re healing a pet because quite frankly its not realistic.
So it comes down to always 2 beacons or sometimes 4? Well what is the uptime of 4 beacons? It’s less than 50% when considering GCD. Beacon is 8 second duration with a 15 second CD but you incur a gcd so in reality the uptime is less than 50%.
Take into consideration that this is basically your best case scenario where you use BOV on CD, in reality you don’t and therefore the uptime is less than 50%. Resulting in overall lower throughput than BOF.
Further, consider that BOF is constantly up on two people. Therefore maximizing the new Beacon of the Lightbringer talent. There are now 3 different positions from which mastery is measured, yourself and the two BOF targets. Again another win for BOF.
Then we move over to mana. While our mana situation is definatley better, constantly casting BOV is a drain on mana relative to BOF which is mostly casted once, then again upon death.
If we consider raid content where you could theoretically get max value from BOV, that is casting BOV on 5 people and healing a 6th (in a raid environment you would have atleast 10 people) that’s where BOV would produce a theoretically higher throughput. But I would still argue this is worse because you don’t really control which targets receive the BOV, it could just so happen to be 5 less ideal targets.
With the increase in holy power, everyone is feeling the ability to cast more abilities and be gcd locked. No one wants to spend an additional gcd every 15 seconds to get BOV out there just for the theoretical gain in a strictly raid environment.
My end take on this (and I would love to hear people who disagree with me and their reasoning) is that BOV was over nerfed and effectively is a dead ability/talent now.
For reference I’m nearly 3k IO and play in M23 keys, these are my feelings.