Allow me to try to answer some of these:
There are quite a big variety of apps but until recently very few official apps. But official doesn't mean better, by no means. Both 6sec and 6tag are better than the official Vine and Instagram apps (on Windows Phone mind you but still). Other than that, it's a fact that there are a lot of missing apps. But when an unofficial app doesn't fill the gap, I found that most of the time, the webapp does the trick (if available). On that note, I do suggest looking into an app called Webapps that allows you to pin webapps on the start screen as if they were actual apps. I love it.
2. Several crashes resulting in phone restarting.
That's not normal nor is it the norm. My phones haven't crashed more than an iPhone or Android phone. There was a problem with my first ever phone which was defective and was replaced with the same phone that worked perfectly well. You should get this issue checked out ASAP (before the 1 year manufacturer's warranty expires).
Again that not normal nor is it the norm. Maybe it's the same problem than your point #3.
4. Gmail and other emails saying they are not up to date
What do you mean? In the default mail app?
5. Songs duplicate on SD card.
Now that I cannot explain nor defend. The Xbox Music app is still unacceptable in comparison to other platforms. Even Microsoft employees have said it should have been kept as a BETA version. That was a bad move. But it's getting better and better though.
These are just some of my issues I have had with these phones. Also, when I first got my windows phone I had to buy a new router because my old one wouldn't let my phone connect to the wifi.
That's hardly the phone's fault
I lost a highschool senior year video memory because after it finished recording it wouldn't save and my phone just restarted.
That's sucks. But that's the kind of thing that could have happened with any phone. But if your phone crashes maybe it's a whole other problem.
Lastly, I wanted to build an app like I did with android, but it's impossible on Windows phone when you have to buy almost $200+ for phone, program, windows 8 64bit, pay to dev unlock your phone, and fee for uploading to the store, might explain why there isn't a verity of apps.
Actually, once you have the phone and Windows 8 you can do the rest for free, even dev unlocking your phone. But the only platform that doesn't require a specific OS for dev is Android. On iOS you have to be on OSx and on Windows Phone you have to be on Windows 8. It's part of the game.
These phones wouldn't be all that bad if it was easier to build apps. I hope these phones do well in the future, but right now they are not for me.
There is an easy way to develop basic apps yourself called the Windows App Studio. You can look into it here:
Windows App Studio - Microsoft
I hope I covered your issues!
Facebook
Twitter
Instagram