How about branching a second table from this one?
We could keep, with some work, a Top N table all the time, and every guard event (I think they're a bimonthly thing) would allow us to update an Over X SED table.

We'd just need to keep the second table over a coherent threshold, based on Top50s.
Right now we have a Top40 table with a base SED threshold of 200k.

Let's say that by next Guards, the Top50s base SED is 324k, then we update the Heavy Hitters Table with a base SED threshold of 300k. Something like that.
The main idea would be to have a glimpse of the heavy hitting players that would be a great support in a Guards event.

I'll admit though, that some kind of player index would be of great help.
Something with data like Name, ID, SED, Lvl, Last Activite Time