Should I switch to WP8? (Verizon)

My Galaxy Nexus is on life support. Every 20 minutes, it stops recognizing the SIM card and I have to restart the phone to make it work. It's lagging like hell now (especially the keyboard). The stock browser (which is the only one I use) seems to be corrupted (weird black boxes where icons should have been). It's battery life has gone from abysmal to unbearable.

I'm still on Verizon's unlimited plan. I want to buy the phone from somewhere other than Verizon so I can keep the data plan. I don't have a ton of money to spend, so buying used is an option. I don't want to spend more than $300 if possible.

I'm now debating whether I should switch to WP8. The things I want to know about are;

Apps - are there equivalents for WP8?:

Easy WiFi Tethering (this is so I can use the hotspot for free.)

Google Drive

Google Now

FB Messenger

Netflix

Spotify

Updates - Are WP8 updates like Android (fragmented), or like Apple (all up-to-date devices get them)?

Updates are important. I bought a Nexus device just so I could get them on Android. I remember Lumia 900 owners were botched of an update a few months after launch. Is this going to keep happening?

Camera - Features?

I know Lumias have very nice cameras. But what I'm looking for, is one capable of something like Photosphere. I use it all the time. I also love macro mode. My Gnex didn't have this, unlike the phones I had before it.

Choice

Is the Lumia 928 the only WP8 phone on Verizon? What other decent phones are there? Should I just stick to Android?