I don't like the idea of focusing on an individual hero. Forces you to taking extreme liberties with the character and create unnecessary situations in order to advance the plot. Just focus on groups of heroes at a time, it's a team game so why try and focus one hero in the first place. Make it a movie about how the dota heroes cope with the ancients, make it a mini series that focuses on their lore and how their lore inevitably intertwines together.

Making one hero the main character just seems so incredibly predictable and trite. Make it a celebration of the dota world, not some predictable love story between sven and crystal maiden where the characters could be interchangeable with hundreds if not thousands of fantasy romance action adventure novels/tv series/movies/cave wall etchings/fanfiction. I also hate the idea of focusing on 1 or 2 heroes because there are only a few heroes who have "bad lore" and I feel it's pretty biased to choose one over the other. If you are going to make a movie about Dota, make it about dota. If you want a generic movie focus on juggernaut.