Has the development team considered decreasing the number of coins earned for solving a block versus increasing the difficulty?
There are so many disadvantages to this, they completely outweigh the advantages.
First, many more blocks would be generated. That would tremendously increase the network, CPU, and storage overhead of operating the bitcoin network.
Second, a change in the protocol would upset settled expectations of how bitcoins behave. They would increase fears that future changes would upset other settled expectations. (By analogy, how would you feel if you worked hard for years to save up $75,000 and then next year the government prints $250,000 for each family? You'd be kind of pissed, wouldn't you?)
Third, the speed of block generation would not be much closer to the speed of network propagation. Many more blocks that are generated would fail to become part of the public block chain. Many more confirmations would be needed before a transaction could be considered stable. The number of reorganizations would go up by orders of magnitude.