SEEKERS: Vaati’s group, the best messages and most considerate summons
straydmn: the reddit group, I should probably drop this one.
fcb: Fighting Cowboy’s group, he’s been streaming Souls games for more than a decade. Good group
ukraine: Because SLAVA UKRAINE!
KNIGHTS: Dom’s roundtable hold’s group. Almost as good as SEEKERS

I mean you can use whatever phrases you want but if your goal is maximum summoning and summons with good messages, use the above list.