I think it would be a fantastic idea to add this to the list of possible Brawlhalla Run. The main Idea is to complete Horde 11%, Tournament and Tutorial all divided by splits and allows the use of menuing on Horde and Tutorial. Only being able to split once reached the objective except for tournament where you will split once you see the top 5 Podium. For a good example watch my vod on it.
Something like this would generally be in a "Category Extensions" leaderboard attached to the main leaderboard. Personally, I see no reason to make this an actual category. I doubt interest would be high, as there isn't a ton of crossover among the existing categories. Some of the categories included are also random enough to prevent any kind of decent time.
If I were to bring runners for the category and a sub 8-9 minute run would it be more likely?