I do not see any place to submit runs if someone was to do an IL run for this game. I personally think that an IL section would fit this game, as you are able to select every level from an in-game menu. So why is there no IL section?

It has been discussed in the past to include an IL leaderboard, however at this time we do not feel the need to create such a thing on this website. All current Sonic Heroes ILs, whether they are the console or PC version, are hosted on the Sonic Center.

http://www.soniccenter.org/rankings/sonic_heroes