I think we are a long way from needing transaction fees to incentivize mining

If the arbitrary block size limit is removed, that is. If not, transactions will be very expensive and Bitcoin useless for most purposes.

For most purposes. With the limit only a couple of thousand (high value) transactions fits in a block. Most potential transactions just can't be made.

i'm fairy sure there is no if about it.  they just need to implement the "headers only" version of the blockchain, so that non-miners don't need to download the whole chain.  the block size limit is only there to prevent the blockchain from growing at an absurd rate (the current limit gives you a maximum of 25GB/year) and getting too large to download quickly, and it currently sits at 115MB.

Even so, we're not anywhere near hitting the current block size limit.  The average block is currently just over 1 kilobyte, and the largest block i see currently is 14K, not anywhere near the current 500 kilobyte limit.

I'm not so sure of that. I guess it depends what you mean by "a long way". The bounty per block will drop in less than two years, and it seems that mining is barely profitable as it is. I suspect a lot of miners will retire their machines once the bounty drops.