The tokens at the end is an awful change for a couple reasons. One, it puts all your eggs in one basket since some groups are terrible and don't end up finishing because people leave. If people want to farm the first boss of a dungeon over and over without getting the coin reward at the end, who the
cares? Whatever happened to letting players play the way they want to Anet?
Two, imagine you're at the final boss and the power/net goes out. Guess what, you just wasted 15-20 minutes of your time. I've seen that happen twice to other people while running CoF and they missed out on the end reward. But they weren't too pissed because it was only 5 tokens.
This is what I'd call a lazy fix for their bad dungeon designers. They're tired of patching the leaking dam since everyday people are finding new 'jumping puzzles' in their dungeons to bypass content. In CoF, it was possible to get 40 tokens a run by exploiting two spots and bugging an event. Their whole 'buff' to daily run is a joke because it makes the grind even harder now that we can't get more tokens per run from chests.
I'm noticing a trend here where they say they want certain things for players and then do the opposite, like not having grinds in the game. Oh yeah, it's called lying.