Is Rugby League more similar to Rugby Union style or Australian Rules Football?

Eric, you basically answered your own question. Union and League are very similar whereas AFL is in cl of its own really. Hence it is "Australian Football League" played mainly in Australia much the same the NFL (gridiron as it is called outside of of the USA) is played mainly in America. NFL, too has some similarities to rugby, I would say more so to Union than to AFL. Hope this helps, thank you.