I think you make it too complicated. Yes, the reward is some kind of inflation maybe but in fact it isn't. The price ONLY get's established on the exchanges and markets. Which means only what all users believe bitcoin should be worth will be what bitcoin will be worth. And miner rewards and other things seems to have no impact on that.
I don't see how it can be too complicated. When miners sell their stash of coins, they are just like any other Bitcoin sellers, and the effect they have on the price is in no way different than it would be if someone else had sold the same coins. The only difference is that they sell newly minted coins. The price changing effect is absolutely the same. If what you say were true, it would mean that the bitcoins that miners produce and sell somehow avoid affecting the price of Bitcoin...
In short, you shouldn't consider the miner's reward in isolation, taken per se, but you should look at the supply of new coins which enters the market and where the reward plays a secondary role as a factor in quantifying the amount of this supply
