Yeah, I think a decreasing block reward was a good idea, but I think it's on the wrong schedule. Following something like Metcalfe's Law, the value increases geometrically but the reward isn't decaying fast enough yet. That means at some point in the "middle", the value of the block reward will be increasing much faster than the amount of the reward is decreasing.

https://www.wolframalpha.com/input/?i=n%5E2+%2F+(2%5En)+from...

That's where we are now, and it means the reward will be large enough to drive bad behavior at least until the next halving (probably two years from now http://www.bitcoinblockhalf.com/ ).