I'd also be interested in configuring my server this way. Super fast, no-delay asura strike!
First thing I noticed, was that there's a delay on SP recovery after Asura strike by default. A quick google search revealed the following solution to that:
It was to modify the file rAthenaRootFolder/db/re/skill_cast_db.txt
and replace/set this value:
//-- MO_EXTREMITYFIST
271,2000:1750:1500:1250:1000:500:1000:1000:1000:1000,3000:2500:2000:1500:1000,0,0,300000,0,2000:1750:1500:1250:1000:500:1000:1000:1000:1000
After a re-compile, I'm able to spam yggberries right after asura. So one step closer Need to find out how to remove delay after skills, and get insta-cast.