Just wanted to post back with an update...
One thing I don't think I mentioned was that I was also on the fence about switching to Android to see what life was like on the other side of the fence. The more open environment, my distaste for what Ive has done with the UI since iOS7, the fact that I could buy a cheap Android watch ($99) if I wanted (even though I don't think I'd really use any of these smart watches anyway), and just the matter of having never tried Android, all had me thinking hard about it.
I was disappointed in the new Nexus phone, since it was no longer an affordable unlocked phone, but I really wanted to try the latest and greatest version of Android (Lollipop), so that had me waiting some more. Then I heard some reports that users are experiencing their fair share of bugs so, like iOS8, it sounds like the latest release may have been rushed out the door to meet the holiday deadlines.
This morning, for reasons I can't even remember, I did an inventory search and discovered that one of my local Apple stores (about 30 mins away) had a Space Gray iPhone 6+ 64GB, which was the 6+ model I originally wanted, and I made an online impulse buy. Picked up the phone at the store and spent the afternoon getting it configured for my use and reconfiguring my iPhone 6 for my wife.
My initial impressions are not positive, though. I'm thinking it may be too big for me. I really like using my phone one-handed and even the regular iPhone 6 was a step down for one-handed use, and no I'm not shocked that the 6+ is a step down from the 6, in that regard. But I was thinking that the larger screen size might wow me enough to overcome that. I'm going to give it a couple of weeks (or however long I think I need to decide) and go from there. If I can decide real soon that I don't like it and also determine that my wife doesn't like it, I could always return it. Or, I can give it to my wife who indicated previously that she might like the 6+ and she claims that she never uses her phone one-handed.
By now, some of you are wondering what any of this has to do with the 16GB vs 64GB debate. Well, of course, it doesn't have anything to do with that. But I did end up holding off on the 16GB and went with the 64GB partially because I knew there was a possibility that I wouldn't end up liking the larger size of the 6+ and might give it to my wife. She's old-fashioned and doesn't use the cloud services as much as me and likes to keep her music stored on the phone itself, so I figured that if I was going to get a 6+ and might hand it over to my wife, that I should probably pay the extra coin and make sure she has enough storage so that she doesn't complain to me about running out of space.