I think a lot of people think their own skill is nothing special. Even some of the top players do. I'm not sure if anyone can be good at judging themselves on that.
I think this is true for people not at the top, to be honest. I don't see Chum, Cactu or Zil ever downplaying their abilities. There are cases where they say things like "I'm bad at micro tapping" or something like that, which is completely different. I know for a fact that Chum knows he's very good, and Zil is about as good.
It does seem to be entirely true for players of other (lower) skill levels. But the fact that both Nameschonvergeben (whom I from now all call Benben here) and Glaceon Mage think they're average when they're both vastly different in skill level can probably be attributed to the fact that they're surrounded by people of just about every level possible. At the top you have people like the aforementioned three and at the bottom you have people who can't 1cc easy mode for their life. In some cases, you even have people here following the Japanese top (E.g Yu-suke, Gobou, KG etc.) so your perception of your own abilities gets skewed even further. That is at least definitely the case for Benben. He follows Japanese players all better than him and is surrounded by better players in both IRC and on Skype. To my knowledge, Glaceon Mage on the other hand is only in Skype so she's missing players but still sees how many people are better than her. The total pool upwards is bigger for Benben but downwards it's the same/smaller. It is not strange for him to think he's average then, generally speaking.
But of course, maybe I'm reading too much into it. w
Though it can be fun to pick a player who's slightly better than you, and aim to match/surpass them.
That's definitely true. I think you can even choose to pick a much stronger player than yourself, assuming you have the base for it or if that better players' run is quite old or something like that. It can be, after all, be somewhat difficult to find a player slightly better than yourself for every category you play. Just be careful not to get overwhelmed by picking someone much better and you're golden.