Switching to Android, help me out please.

Hi Everyone,

I am switching to a Nexus 4 from an iPhone 3GS (running iOS 6).

Please help me with the following:

  1. Privacy:
    1. I am planning on making a new Google account for the phone so it is not tied to my normal account. Is that crazy?
    2. How can I make sure apps I install are not stealing my data? Apps that modify Android seem to request access to everything on your device. Even normal apps want crazy permissions sometimes.
  2. Customization:
    1. I am tentatively planning on living with 100% stock Android for a couple of days before messing around with it, just so I can get a feel for Android. Waste of time or worth it?
    2. Help me find good tools for customization and tell me what I might not know I should be changing.
    3. How much can I change the phone without installing a different ROM? Is installing a different ROM worth it? Positives and negatives of customizing stock vs installing and customizing a different ROM?
    4. I am not such a fan of many elements of the Android UI. How can I change them? Maybe I should just install a ROM like MIUI?
    5. Alternative app stores. Yes or no?
    6. If i really don't like Android, is it possible to install WP8 on a Nexus 4?
  3. Living outside the US
    1. Could I use the US play store? (A search online seems to indicate not). I would like to buy stuff using Play cards (someone in the US can buy them for me). I would much rather see dollar prices than my local currency.
    2. I am going to need to text some people with dumb-phones in the US (two way calling will not be an issue on my cell plan, just texting). I need a text-over-internet app, preferably one that integrates with the general messages app. Recommendations?
  4. General stuff:
    1. What should I know going into this?
    2. Cool features, tips, and tricks.
    3. Everything on Android seems to be bundled as an app, including icon packs, wallpapers, etc. What is up with that?
    4. Battery preservation tips?
    5. [Added Oct. 2] Android multitasking confuses me. Apps (I'm looking at you, Waze) seem to be able to still run even after they have been quit from the multitasking menu. Are there any rules to how apps can run in the background?

Things to note:

  • I am not afraid of getting my hands dirty. (I have no problem installing ROMs, etc.)
  • I am switching to a Nexus instead of a new iPhone for situational reasons.
  • I already have the phone and am not considering other options. (Yes, I know there will be a new Nexus shortly but it is not relevant to me.)
  • I care a lot about privacy. I have Ghostery installed on my browsers, etc. Obviously I use apps that access my location, and all my email is tracked by the NSA, but I try to minimize the damage where I can.
  • Feel free to answer with a simple link to somewhere I can find out more about all this. I don't know of any Android resources...
  • ... pointing me to helpful Android sites, etc would be appreciated.
  • I do not expect (or want) Android to look like iOS, but a lot of the Android UI just rubs me the wrong way.
  • [Added Oct. 2] I have not set the phone up yet, so if there is anything I should do during setup let me know.

Thanks for reading through my wall of text and taking time to answer. Have a good day everyone.