The world first thing is untrue I mean the world first videos are on youtube did you not search them before posting this?...no BLM in T6, T7, and T9 (in fact they took two SMN's for T6 and T7 <.<) for second coil so you should check first before saying something like that :x
SMN was widely taken over BLM for Second Coil in my experience when I played during that time. I actually played SMN as my off job instead of BLM during Second Coil since it was more accepted in my experience especially because of T7 Renaud kiting. In my opinion and experience the only turn BLM probably would be a better choice over SMN was T8 since the boss was a stationary striking dummy.
Seems first coil world first videos had SMN and BLM in them cept for T5 which took BLM only. First Coil T4 world first video actually used double SMN too due to the large amount of adds and dots went through the knight shields. That happened in my group for it too actually our BLM went SMN and we double SMN T4 due to the large amount of adds in it and also the dots going through the magic shield. So in my experience SMN was intermixed with BLM during first coil and your world first example has BLM and SMN in most of them so equal.
Final Coil world firsts on youtube did only take BLM though, but that's only 1 out of 3 tiers so not bad at all.
I mean in my experience playing through all of this and completing the raids as a healer and a caster sometimes BLM wasn't always taken over SMN until creator like you are claiming here so it is better you don't talk in absolutes as if your opinion is a fact :/
Where are you getting this statistic from?
In the end though I don't think BLM needs raise. To me it doesn't seem like that is the problem with the job. I personally switched to off job RDM instead of BLM because BLM mobility makes me cry and the fights require a lot of movement again so to me I just don't feel like the hassle is worth it. I've seen some very good BLMs though in this tier savage, but I think SMN after they buffed its play style kind of just overtook due to how much damage they do.
Raise wouldn't fix anything really since groups don't rely on raise....a DPS job best feature is their DPS and raid DPS contribution. During progression Raise helps yes, but the healers would always be better off managing raises than making a DPS job interrupt their DPS rotation to raise.