You know, considering that one purpose of the coin drops is eventually to get to zero and have everything be running off of transaction fees, perhaps some adjustment to the transaction fees should be made near these jumps so as to get some (not all) of the lost-gen in as increased fees? I know that I hate paying fees myself, but if a block only generates 0.1 BTC for whoever creates the block then we're not gonna see much difficulty by the time we get to that point.
Any drop in difficulty when we get to 25 BTC I don't see as that problematic, it's when we get to the lower levels that I'm more concerned about long-term damage.