See my
replace-by-fee-tools, specifically
bump-fee.py for an alternative based on increasing your bid. Not always convenient by itself - fee estimation is still useful - but being able to increase fees after the fact lets you be much more aggressive in your fee estimates.
Yeah, but this isn't trivial to implement and also creates additional traffic.
Sure, adjustable fees is a solution, but there is a long way for it.
Besides, one approach to the problem does not exclude another.
Just to be clear, the above is a complete, working, implementation of the idea. Any wallet software that handles double-spends and mutability correctly can implement it without much difficulty.
I understand. But it is a different approach to the solution.
Some people want to just send transaction with a fee that the minters require at a certain moment in time.
And then they want to forget about the unconfirmed transaction, knowing that it will be mined as soon as any of the miners, asked for the minimal fee, brings in a new block.
Your proposal is about waiting for a transaction to not get confirmed - and only then increasing the fee.