Something to keep in mind is that reducing duration, decreasing cost and increasing the cooldown might very well have the unwanted effect of increasing munitions float which would result in spamming the flares and Concentrated Barrage and the Valentine Sexton barrage even more because it'd reduce/eliminate munitions management. Which might not be much of a net improvement.
What about adding 3 red flares to concentrated barrage so the enemy can actually see it if he doesnt have his screen on the current flare at second 0

would make this ability a lot less frustrating.