Congrats on being Chessity's number one champion. All I ever do on that site is route planner.
Thanks, but I think that's a bit of a silly category they have on the leaderboard. The "champion" measure is mostly a matter of whether you have 100% activity or not: you get 5% activity per day if you do at least 20 problems, so if you've done that every day for the last 20 days, you have 100% activity and will be high up on the 'champion' board. My tactic rating is not very high compared to lots of others on that site, but the serious players who have much higher tactics ratings than me must not train at least 20 problems a day.
I am pretty sure that rating does affect your champion score; I saw this in one of Janton's forum post. Also, I have a 97% activity, but my rating is only 1479, and I only have a champion rating of 245.
Maybe yes. But white starts with an advantage, being up a tempo.