As a pilot in my younger days, I was extra horrified by the events leading up to the occurrence of the mid air collision over the Potomac the other day. Boring initialisms and vague warnings were calmly droned by air traffic controllers as they watched a helicopter head straight for an airliner.
There
need to be two warning levels that are said with two levels of distress in the voice that any human brain will understand "FLIGHT PATH CONVERGENCE! FLIGHT PATH CONVERGENCE! FLIGHT PATH CONVERGENCE!" (or something similar) naming the two aircraft, then if they don't change course YELL "CRASH CRASH CRASH!". And I mean YELL!!!
I barely avoided a mid air collision over beautiful Half Moon bay one sunny afternoon flying a Cessna 172 many years ago. I can tell you, when you're closing head on at over 200 knots you don't have a lot of time to be calmly discussing flight adjustments using initialisms like which plane your about to crash into. That dot quickly turns into an aircraft and you turn or you die.
Luckily we're humans and there's built into language a system illustrating the order of magnitude of the imminent threat. It's called yelling and it has its place, but ONLY if a crash is imminent and as a last resort. You hear 'FLIGHT PATH CONVERGENCE!" or worse, "CRASH!" yelled over the radio you look all around you snap your head around as quick as possible and get ready for a hard bank in the other direction.
I'd propose creating even another level of warning. I know this goes against current protocols to be calm and collected on either end of the transmission between tower and aircraft, but clearly there might be times when calm and collected isn't the right approach.