The level 80 upgrade allowed a lot of crazy stuff that wasn’t possible before, including perfecting my Melee/Pistol hybrid zero build! Or as I like to call it, Pistol Whipping 
By perfect, I mean it provides access to absolutely every skill you want. Since you’re using pistols and melee, you don’t need At One With The Gun or Critical Ascension; since you’re using a Legendary Hunter, you’ve got no need to max most of the level 1 skills. While you could get some benefit from Fearless, it tends to take your guns over the 10.0 Fire Rate threshold, which makes Two Fang stop working, so it’s ultimately not really worth it.
Now for weapons.
Obviously, the first gun you’ll need is a Rapier. You might be tempted to use a Law+Order, but with the Hunter healing on Deception, plus Many Must Fall, plus Resurgence, you’ll be keeping yourself well topped up the vast majority of the time. Plus, you’re looking at a very short cooldown on Deception, which means Innervate will be active about 50% of the time. All in all, the increased melee damage more than overcomes the healing.
The second gun you’ll want(ideally, anyway) is a Dva Stalker. You want Dva because you want Two Fang to work, and if you go for fire rate, Two fang won’t provide the bonus you want to get. The Stalker is an excellent choice for this build, because the bouncing bullets create a high chance of random bounces hitting enemies after boring your main target, and dealing heavy damage.
Other options include the Tattler, Slagga, Infinity, or even the Bane. This Zero can counteract the weaknesses of the Bane using Execute, so you can use deception to get close, then unleash a wail of bullets that will demoralize your enemies and confuse and terrify your allies. The Infinity would require some tweaking, as you’d obviously want to spec One Shot One Kill with it. Honestly, I think that’s a better option for a more sniper-style build.
For a shield, you’ll obviously want a Roid Shield of some sort. Hide of terra is fine if you don’t mind all the explosions. Otherwise, a Punchee is easy to get and straightforward, so it makes for a convenient option, if unexceptional.
You’ll obviously want the Legendary Hunter class mod, keeping you hitting hard and in deception constantly, plus the healing keeping you up and hurting enemies.
The rest is pretty self-explanatory. Open the fight with pistol fire, weakening multiple enemies, when you start getting low/your shield breaks, use deception and Many Must Fall to quickly clear out the battlefield and heal up. Your shield will reactivate at some point, bringing you back to where you started.
Rinse, Repeat.
Giggle as you invisibly rampage across the battlefield. Really, it’s pretty hilarious.
Anyway, hope you enjoy the build, I certainly do.