Anyway, the main benefits are a keyboard that works, plenty battery life, useful apps, and probably $50 or less. Feature phones especially have terrible keyboard/numpad combos that hurt the thumb. Just having a real keyboard... well, a two-thumb board if we're honest... was a serious improvement. Ended up finding hundreds of free apps online, too.
http://www.ebay.com/sch/i.html?_from=R40&_sacat=0&_nkw=black...
I don't think using a feature phone is desirable unless you really only want to do calls (using the phone network, not e.g. Skype) and text messages (again, not using Whatsapp/ FB messenger etc.). You would miss out on Maps, traffic information, (most likely) the option to sync your calendar and contacts, ...
Instead, manage your smartphone so that it becomes less distracting, e.g. by disabling all but the most important notifications. Or leave it off sometimes.