Don't slot your future doppel card in a jamadhar[1]. Instead, buy a +10 Specialty jurs[4] if you can (I'm selling one for 300k, very cheap compare to others) and save up for 2 doppels and maybe 2 Alligator. You can sell this a lot easier later on than a Dopel Jamadhar[1].
If you're going crit sin, you won't be needing much (if any at all) dex since crits ignore flee and 0 int. Since you're not 99 yet, I wouldn't recommend going 99 agi because you waste more stat points getting it to 99. Instead, distribute the stat points evenly out between str, agi, and luk and maybe a bit into vit for some extra hp and defense. About 45 luk should be decent enough with your gears.