The Fire damage type is so much better then disease in optimized groups with how many modifiers that buff it with 100% uptime from engulfing giving 6%, and 66% uptime from encratis giving 5% damage while active giving and effective 3.3% damage overall a long fight, along with the 10% damage that stalking blast bones gains which interactive multiplicatively with these other benefits resulting in a net loss of ~20% damage in optimized groups.


The guaranteed disease proc that is now on blighted blast bones adds about 6% damage to Blast Bones now only being a net loss of 14% damage or so

Then with the passive changes gain 2%crit with 2 grave lord abilities on front bar giving with most builds 125% damage 4% of the time for 25% of the health pool giving a net average damage gain of 1.25%

Some changes such as a damage buff to the blast bones of slightly over 10% would entirely mitigate these nerfs

Theoretical changes that would allow the skill expressive build to not suffer would be the 15% Grave lord damage and DoT damage buffs from the changed base morph to be gained briefly after casting blighted blast bones for 5 seconds, applied to the caster as a 5 seconds buff if they're in detonation range of the blast bones, or applied to enemies hit by blighted blast bones as a vulnerability from the caster for 5 seconds. (The 5 seconds would be so need to be skill expressive to keep the buff uptime up, but has some forgiveness of miscasted or moving targets)