There are a lot of reasons your hops could be muted. Many of them unrelated to the things you discuss in your post but we'd need to know much more about your processes to identify where you should focus.
Having said that... the MO that gets me the freshest, most aromatic IPAs absolutely does not include a secondary vessel.
The good news is, if you're kegging it's simple! When your beer has reached terminal gravity put your dry hops in the keg in a paint strainer bag or mesh container like a hop sleeve and rack your beer into the keg. Let it sit at room temperature for 3-5 days (on or off gas) then chill it. I leave the hops in the keg until it kicks, sometimes supplementing them with more if the keg lasts a long time and aroma starts to diminish. In my experience the DH at room temp brings out the best aroma. Going straight to the cooler tends to mute it a little IMHO.
As i mentioned above there are processes that can be utilized with IPAs to help focus on hops. Things like increased sulfates in your water, focus on kettle pH and timing of hops during/after the boil.
Increased sulfates can improve perceived bitterness, pH as well. If you want more aroma don't do "flavor" additions with hops, save them all up and use them in the last few minutes of the boil or after flame out in a whirlpool.
You also want to be very very careful about oxidation since it will flatten hops aroma and taste quickly. UV light skunking happens fast with IPAs too. Just a few things to think about. If you post more about your process others may have some suggestions for you as well.