There are so many moving targets here to potentially throw it off course. A bitcoin price crash,
You'll be mining the same number of bitcoins, only they'll be worth less. That's a fail.
Better, but unless you mine more bitcoins than you would have, had if you bought bitcoins directly instead of buying a miner? Another fail.
That's because it is irrelevant. Simply assume that you have bought bitcoin instead of the miner, and hold that bitcoin. Your bitcoin will be on the same roller coaster, so you can factor out the fluctuating price.
If you mean difficulty going up, that's no surprise. All the preorders & all the chips hitting the market is a one-way sign for difficulty. The "S" in ASIC stands for specific, these babies can't be turned into gaming rigs -- they could only be mined or thrown out. Unlike GPUs and CPUs before them, they can't do anything else.
True enough, we can't say the sun will rise tomorrow & be 100% certain. Though it's reasonable to bank on it, and not the unlikely chance that The Spaghetti Monster will decide to shut down the universe.
"Flogging the miner at the end" is irrelevant. There isn't much difference between making a nickel a month & 6 cents a month. See difficulty curve for explanation.
If it's fun, it's fun. Can't argue with that.