what is some of the most promising project in terms of dividend paid out to coin/token holders?
Well, NEO is a top 10 token, has a lot of potential for growth in 2018. (a lot of announced development), it's dividend is paid in the form of a GAS coin.
From the less known there is a very interesting platform called eXRN, it's development is rather steady and it's not worth much so it means that if anything is about to happen there the gains will be huge. "A dividend" is called eXRT.
Contrary to my expectations, eREAL has a steady development. They promised dividends but for now they weren't able to hand out any, but maybe that will change.
Those two may not be your average safe bets, but worth checking for sure.