I have tried a Katana and a Broadsword.
Katana does too low damage.
Broadsword is 1.25s with 155 stamina and 35 ssi but usually I have just 100-140 stamina, so my speed is 1.5s-1.75s...
p.s. The broadsword is Elemental Slayer, 30 SSI, max HML, 35 DI, 40 HSL.