This is a nicely done model, and surely useful. You need to lower that particle count, though. It almost reaches 500 particles in regular animations as Stand. Not only it is an overkill of effects visually, but also each particle mean 2 polygons to be processed. You can achieve good results with fewer, but bigger, particles. Just to give you an example, the Firelord, which is a particle heavy model, has around 90 particles at its stand animations. You shouldn't go above that in this model. Play around with their size, opacity, fading, etc, and you'll see how easy it is to get good results.
In addition, those particles leave a trail in-game by the hero's shoulders. That doesn't look right. Trails left from weapons, or staves, do look alright in-game, but you'll probably do better setting the shoulder particles fixed to Model Space, so they don't spread around in the game scene, and your model should then leave 1 single trail of particles, which seems much more reasonable and looks better imo.
If you have any doubt on how to solve those particle issues, feel free to contact me.
The other issue I see is that the death sound it uses doesn't correspond to the death animation. There's a very present impact sound of the corpse hitting the floor around 1 second after he already fell down. You might want to change that sound (or the animation)..
Except for that, it's a great piece. Useful for a cinematic/campaign hero, since it has many talk animations. Fix those issues and we'll be good to go.