The conjured weapons are the best/ the fiery sword at lvl 30 can get to 1k damage in a single burst. where they shine though is when you give them to a dps. the can wreck. I have downed bosses in seconds with conjured spam.
I see the idea behind them. quick burst of power from a utility. but due to the low cool down u can keep them up if no one picks up second drop.
Now here is where you can make them truly shine. as i have done in pvp. You remain in water attunment and pick up 10 traits and get the 20% bonus when weakened. Then pop over to lighting max that and get the 60% chance to weaken. Now max fire and pick up 10 more conjured points and 5% fore dmg increase. take the precision signet.
so in a fight open with precision signet follows but conjured weapon spam. its about a 30-50 increase dps depending on conditions.
i can down people in pvp in about 6 seconds with ult. i have wiped entire team before once.