I ported my number into google voice so I don't have to pay for texts (god, text messaging -___- getting people to adopt mobile messengers is the hardest thing on earth) and mostly so that I can block people

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For my setup, Android works best.
I would say Nexus because you always get updates first and you won't be stuck on a gimped Android.
If you haven't tried "stock android, I'd recommend you do so because it's quite a better experience than an "OEM" themed/skinned/modded version of android. It's similar to different flavors of linux, except Samsung and HTC both take giant ****s into what Google made and turned Android into a giant abomination (not that stock android is an angel by any means).
You can also flash it out to your heart's content if you are into that.
Whenever you buy a "flagship" phone that runs "Android" it'll devalue quickly in 3 months or so. You might pay 299 or 199 for that phone but in 3 months time it'll be free or 59.99, 99.99 you get the gist of it.
You're also stuck with that phone for 2 years. I had a Nexus 4 and I sold it and got a Nexus 5. I'll probably sell my Nexus 5 when the 6 comes out at the end of year/early next year.
Iphones don't devalue the way Android phones do (well at least they didn't used to) but iOS isn't conducive to my setup.
Oh so you're using Verizon.
Well ... good luck! Get an iPhone!
Maybe try looking into a Google play edition phone, You can also painstakingly (well from a Nexus user's perspective) mod some of the phones into a GPE device. I did that to an HTC one m7.
My 2 cents.