One of the difficulties about forum discussions concerning Fleet Shards is that the majority of players find it hard to perceive of a Fleet Shard that’s different from their own,DarkHelmetBnB
Sure, there are Fleet Shards where there is a welcoming ethos, where someone who asks to join a coordination server on Discord will be allowed to join with open arms. But there are other shards where this is absolutely not the case and new members will not be admitted.
You describe a Fleet Shard where there are inactive accounts in your top 50, and I know of guild mates who have even more desolate Fleet Shards than that, but there are a handful of outliers where there are hundreds of active accounts. On a recent camping trip, where I had pretty much no access to cellular data, I fell below 150 in my Fleet Shard and all I could see on my return to the upper ranks was 7* Leviathans everywhere, all with very active owners.
I have sympathy for people who are wilfully excluded from claiming top payouts by the actions of others. But the suggestions made by the OP will make Fleet Arena vastly worse for the player-base as a whole.