Here are some Fanon abilities for Hinata/Neji I came up with.
Byakugan - Opening of the Mind's eye: An ability of the Byakugan that allows for two or more users to share each other's eye sight. The number of people that can link up and the distance they can be apart from each other depends on the skill of the user
Gentle Step: Twin Lion Blades: The Lion Fists that form around the user's hands will have one sword in their mouths each. This will extend the range of attacks of the user as well as severe chakra tubes.
Gentle Step: 64 Twin Lion palms : A combination of Twin Lion Fists and 64 palms, as Hinata hinted to in chapter 633.
Gentle Step: Twin Lions Burst: An attack that combines Twin Lion Fists and Air Palm for a ranged attack in the shape of a lion head.
Gentle Step: Twin Lions Barrage - 64 Bursts: Similar to the previous attack, except with 64 ranged attacks rather than one.
Summoning - Twin Lions: A summoning technique that calls upon one lion and a one lioness. Their sizes are about the same as Kiba's 3 headed Wolf form.
8 Trigrams - 64 Heavenly pulls:A technique that uses the Gentle Fist to dislocate 64 joints, causing the opponent to be incapable of moving.
8 Trigrams - Chakra Senbon: Senbon Needles created out of chakra and are executed the same way as Kaguya used her hair needles. Their purpose is to aim at chakra points.
8 Trigrams - Air Palm Barrage: An attack combining Air Palm and 64 palms for a multitude of chakra blasts.
8 Trigrams - Air Step: Rather than releasing Compressed Air from the Palm in the form of Air Palm, the user Releases compressed air from their foot, enabling them to step through the air in a fashion similar to what 8th Gate Gai did.
8 Trigrams - Guardian 64 Palms: This was actually a filler technique, but It'd be cool if it became canon. It functions similar to Heavenly Rotation but has more offensive properties as opposed to Heavenly Rotation, which has more defensive properties.
8 Trigrams: Gentle Slash: An ability that is similar in concept to the basic gentle fist, except that it can cut the chakra tubes in half.
Gentle Fist art - One Blow Beam: Very similar to One Blow Body, except the chakra shot out of the body is a lot more compressed and dense, making it far more lethal.
Gentle Fist art - Body Blast: Neji has actually shown this ability in canon (against Kidomaru's Spider Summoning), though it was never actually given an official name, so I thought it would be nice to title it. The technique works by inserting so much chakra into the opponents body, that they explode from the inside