Welcome, I was a long time Android user (since the "OG Droid" days) and made the switch a couple months ago as well. It was definitely a bit of adjustment as you've found out yourself in some aspects, but overall the experience is great. As far as the 16x9 thing goes, I'd just take it in the normal 4:3 ratio and then crop it to 16x9 if you really want a widescreen effect. Many phone cameras that offer both ratios already are doing this. I think the higher end Lumias were the exceptions.
I have to agree about the stock keyboard, I was using swiftkey for years on Android though so the ability to use it on iPhone now really helped. It's not quite as good as the Android version, but close enough that I don't mind much. I never use the voice dictation function anyway. The only thing I really miss vs. the Android version is long pressing the letter keys to get numbers, symbols, etc.