I dislike the ideas of super characters because then they become almost obligatory. Is there really any marine army that would be better without Vulkan?
I don't take him because I don't want his over the top benefits. I just want a regular captain to lead my marines. Not an invulnerable super hero who has campaigned across the universe banishing greater daemons and liberating galaxies. Those type of characters could be fun occasionally, but how about just a guy who has a chance of doing something awesome? Way more interesting in my opinion.