I've requested for it to be shown on everyone's profile before. I think it would be a nice addition to the profiles. It's already a 'ranking' as such so I dont understand the 'official' idea.
With regards to the weighting, I havent seen a perfect system yet. Indeed it currently weights popular events a lot, while not competing in difficult events such as 5bld is not 'punished' much. I've calculated proportional sum of ranks before, but then events with less people are weighted quite a lot. One could argue that having a high ranking in an event with less people does indeed indicate all-rounded-ness so it's not a problem at all.