People invest in mining coin because of what it can be. Not for what it is today. More fees spread over more transactions is definitely in their interest. If core devs insist on keeping this veneer of control, they would be wise to compromise for 4MB in 2016, and doubling at the halvings.
Nah, I'd suggest that most miners are in it for the block subsidy right now.
Now, when that goes away and the richest of the rich, well, those who want to keep their currency movements secret, well, those who don't have the "right contacts" to do it for them in the demonstrably corrupt banking system have Bitcoin usage down to a couple of transactions an hour, I guess someone will fire up a GPU miner for beer money.