Another thing to take into account is team format. Those tournaments tend to bring in more players as there are a lot of Japanese players who view team tournaments as more inviting and more casual friendly. The 1v1 tournaments are seen as more for the better players so a lot of lower skilled players tend to shy away from them. Think back to the biggest tournaments in Japan. For SF, the biggest tournaments are Topanga Charity Cup, a team tournament. For 3S, its biggest tournament is Cooperation Cup, another team tournament. For Tekken, Master Cup gets the biggest numbers, which is another team tournament.
I know it's not in the spirit of traditional EVO, but it's something to consider. You might upset foreign players going to Japan, but I think the average player in Japan would prefer it that way. I feel like stats prove that.