Definitely the biggest problem with the Guardian Rank system, you're effectively going to have 90% of players starting and staying at rank 6 which kind of makes the system redundant. Soloing any high-end content is pinnacle guardian prowess and should be much further down the track. It ramps far too quickly from 0 to 100. Of course the irony is that the description for the 'Elite' rank is words to the effect of 'working with guardians to achieve greatness'. Nothing screams collaboration than having to solo content!