At this stage I think I will let it be, but if (towards the end of the signup process) it looks like there's one team which is clearly significantly favoured to win I might ask if they wouldn't mind changing it up.
I wouldn't mind running a tournament with
several two-top-10 teams but if there's only one it might be a bit lame.
That being said, running tiebreak games instead of a finals bracket at the end should hopefully result in interesting games at the end (if tiebreaks are required, of course).