Asesina is a nice agility class. It's fourth skill is really nice and the illusion is cool too (thoug the cooldown could be lowered a bit.)
Second skill is nice but 3 seconds allows you to only take one or two hits with that armor ( and it's a buff spell that's dispelled when cast illsuion which kinda makes it a bit less appealing. Either upgrade duration a bit or make a skill that helps the hero dealing even more dmg (assassin are good are killing right ^^). So, what I would suggest is something like a counter attack passiv ability (ninja's skill
Something like 10%-15% that when hero is attacked, (taking dmg) the hero counters with a glaive attack (its automatic so it doesn't actually interrupts the hero's attack). That deals 1.5* agi to attackers.
The third skill is cool, because it makes some Aoe dmg which helps in creep killing. But 2*agi isn't good enough on my opinion. I would then make a second passiv skill that makes attacks bounce (lsome dmg loss per bounces). That way, your Arma dmg actually helps in your creep killing ( And it looks cool too).
Both passiv should apply to illusion also.
I know I have some weird ideas sometimes, but they are inspiring some of you ^^
Feel free commenting.