Emmanuel_Capricorn
I think you should try elemental manipulation. Especially fire bending like Azula from Avatar. He already displayed signs for fire affinity after conjuring his blue/white flames in the fight against shift in the movie. Plus with him having two chis/energy Yong and Yang it seems pretty similar to lightning bending in avatar. And I think controlling fire, thunder and lightning would fit well with the theme of Shens cannons. He would basically become sheens strongest cannon himself. Also have you ever thought about when’s discovering his own inner peace and teaching him chi manipulation. This would be interesting.
You can use the idea I gave to you some chapters ago. Also, you can use chi to copy the Herculean method from Marvel, especially the control over body part. Tai Lung could do that (idk if it's true), but the method will increase his control over his entire body. That way, even his hair could be weapons