Hi there,
I personally feel like this isn’t exactly a Bedrock-friendly gamemode. After all, some players will be on phones, Xbox, Nintendo Switch, etc, so it’s not exactly fair. I personally feel that FFA is a touch boring, but we all have our opinions.
On the other hand, it might not necessarily have to be an entire new gamemode, it could just be an area of the lobby where you can PvP, which could be quite fun.
But overall, I think Survival Games is as good as it can get for Bedrock Edition. Thanks for the suggestion anyways :)