Not sure if this will grow into a regular event (hope so, as the format is interesting), but if yes, single elimination is a good format to find a winner (if you want to have more exciting event and are willing to pay for it with some increase of randomness), but not good to choose 8 people to stay and 8 who end up going out (as a single match decides this and if you lose it you are out at least for 7 weeks).
Instead, the ladder could stay exactly the same with regards to finding the winner, but people who lost would continue playing (being paired against other people with same record) for 3 rounds. After those rounds we would end up with:
- 2 people at W-W-W record, who would play for tournament win and be sure of staying
- 2 people at L-L-L record, who are relegated
- 6 people at various 2-1 records and 6 at 1-2 records, who could play in relegation matches, 2-1s paired against 1-2s with 2-1s getting the privilege of side choice in third game if it is needed to decide the match.
This moves most of relegation deciding games to last week (and makes relegations a bit less random) and gives players some more games while leaving the main ladder (used for deciding the winner) completely unchanged.