Very unlikely. Tx fees are likely to remain low. Then again the purpose of mining is to secure the network not get rich quick. As the value of BTC rises the nominal amount of BTC paid in fees per tx will decline. The rise in tx fees will partially offset the drop in subsidy but we are unlikely to ever see a 50 BTC block again (baring some insanely expensive one time mistake by a user). When the block subsidy cuts again to 12.5 BTC we probably will never see 25 BTC blocks and etc.
Certainly an overestimation on my part ...but as you say the value of BTC rises, the amount paid in fees will decline... as a result of smaller units of coin necessary in transacting an equivalent fiat value? -to be sure I understand the logic.
How do you imagine block rewards to look then as the volume of transactions increase, and more emphasis is placed upon transaction fees in determining prioritization? I understand there's limits to the block size, so that might be something to counter growing transaction fees there as well. However, might smaller transactions allow for more transactions in a block?
*snip*... it wasn't long ago that I saw a 6-8 BTC bonus of transaction fees on a block solved by Slush's pool.
https://blockchain.info/block-index/438711Found the block in question, only it was 10 BTC in transaction fees. Certainly the largest I've seen to date.