Sorry for late answer. My main argument is - as I said - the large number of reddit tournaments in the Best Waifu Index. I try to include tournaments from several different communities, even if they are relatively small. That's why I included the ACGN Miss Anime Tournament or the animeclick tournaments.
But of course you can calculate a related index, which includes /r/anime's 24 Hour Best Girl Contest. (Would add 200 points to Sakurajima Mai, 100 points to Shinomiya Kaguya and 20 points to Rem and Hayasaka Ai - if you choose 200 MAXTP; in this case Sakurajima Mai would claim the 2nd overall rank.)
Discuss other moe tournaments here.