I think you need to promote your asset more. I knew about it when I read this thread so if you didn't post this maybe I and many others won't know.
I don't know the market of free character assets here on itch.io but character animations such as hurt, death and fall are important so missing them makes some people, at least me, has doubt to download it. Moreover, the hurt and death animation in premium version aren't convincing, giving even more doubt to buy the premium version. The death animation is like "I'm getting sleepy, let me rest for a bit" while the hurt is "Eh? what's that?".
That being said, maybe I could download the free version so I could edit some sprites to create hurt, death and fall sprites myself.
So my suggestions are:
1. As mentioned above, you need to be outstanding. Specifically, make the sprites look great and add more frames for each animation. Especially in this case, make hurt and death animation more convincing. Add facial expression etc.
2. Make basic animations such as hurt, fall and death be available in free version. In premium version, have some of these animations: punch, kick, spellcast, run, jump punch, jump kick, running punch, running kick, cheer, block and dodge. Each punch, kick and spellcast could have more than one version.
3. Team up with game developer to create game with your character assets in it. Maybe you'd need to compromise by creating assets that they needed. Either way, ask them to credit you in game's page. People playing the game would know about the dev and might know about you too.
The #3 suggestion will really depend on game's popularity but IMO character assets being used in a game have better chance to be known than assets not used at all.