Also have long researched all available options and consider me, but all in all any smartphone over 300 is simply too expensive to me.
Thus I have the HTC Desire 816 a great compromise.
At first it looks natural compared to my One S absolutely huge - but you get used to very quickly to the big screen, it's just indescribably convenient if you want to see something in between the Internet or typing messages. Sure, the phone still some getting used to, but it will come. ;)
The display sharpness and color reproduction is absolutely satisfactory for me, the camera takes great photos.
Sound quality for calls properly. Into the phone book, I came with my previous phone a little easier, but I feel this not as criticism.
Menu as usual HTC, think it's great that not so very many apps are preinstalled or some are also summarized in groups. Thus, it seems overall a bit "cluttered".
Battery performance I find absolutely sufficient, on the first day despite many upgrades and installations and gimmicks (you are, after all curious about what the new part can be so), the battery lasted but all day.
The charging time can perhaps be regarded as in need of improvement, but are ca 3h. Me personally, this rarely hurts, because I charge the battery at night.
The housing acts stable and well-made, though mobile is also so well in hand, but I prefer to use with mobile phone pocket, I am always a little too risky, that it accidentally slips out of my hand. In addition, as the display is scratch-free.
All in all, I can only recommend this phone, seeking a normal, acceptable priced smartphone for everyday use. Send for the "normal" phone calls, messages, surf the internet and a couple of games it is really highly recommended and absolutely enough in his functions.