The first choice in selecting a phone is the carrier. Choosing the best phone in the world, and using it on a carrier that doesn't have coverage where you need coverage, isn't as good as a $20 feature phone on a carrier that covers the areas you need. (Simple Mobile uses TMobile towers, if you're checking coverage. But it's owned by American Movil, so if you're the type who has to call tech support, I wouldn't go near them. The checkers in Walmart know more about cellphones than AM's tech support people.)
Once you choose the carrier, choose among phones that work on that carrier. If it's AT&T or Verizon, stay away from Samsung. They've gotten into bed with AT&T and Verizon to produce "corporate phones" - great if you're the company CTO and worried about corporate security, bad if you're not.
I wouldn't buy a phone without a removable battery. Expensive batteries cost around $20. Having an internal battery replaced could cost 4 times that much or more. And if the battery ever goes into thermal runaway, it's easier (and cheaper) to pull the back off and shake the battery out. (Then get as far away from it as you can - lithium batteries seldom explode, but it's possible, and lithium burning into your skin requires hospitalization.)
I wouldn't buy a phone without an external SD card. You can't use them as freely under KitKat as you could before, but you can carry a few TB of video (or any other data, including alternate ROMs, if you're so inclined) in a shirt pocket.
Other than that, it's really a personal choice. Not all 8MB cameras produce the same quality pictures. Not all screens look the same. Go into a few carrier stores, handle the demo phones (they're real phones, with real numbers, you just can't walk too far from the counter with them because they're chained down.) See how the phone feels - the size, the weight, the "build quality" (does it feel like a cheap piece of plastic or does it feel "solid"?) See how the screen looks with different apps and videos. Make a phone call and see how it sounds (both ways - if the person you're calling hears you muffled or distorted ...) Listen to some music. Play a video. That's how you decide which is the best phone for you. Just because I think a phone is the greatest one ever made doesn't mean that you'll even care to consider it.