Personally looking forward to WC3 story campaign being ported. But yeah I think LoL port is gonna be obvious, just for fun and also because well they can do a lot of interesting stuff with it.
Custom games are coming, but then again they were coming last TI. Hopefully by now shit's almost done for a post TI release, would be a nice way to ride the hype following the event which will probably make some noise even outside of dota itself due to the retarded numbers, if like the week after they start spamming gaming news website with custom game modes shit, a lot of people might check it out.