Hearing is largely a brain function and that in turn can be a matter of training. Help from others doesn't hurt, but listening carefully to live, unamplified live music in different venues is the best help, I think. One problem is a piece of equipment in a system can sound better in some regards and worse in others. Also, you need to live with equipment changes for a bit independently of burn in to let your brain adjust and see how comfortable or not you become with the changes. It is really tricky business, but having live music as a reference really helps. I was amazed at how fast our group could agree on what was overall very good or not.
Headphones of any type lack dynamic impact. That is my problem with them. Fifth row center orchestra seating in Grady Gammage auditorium during Mahler's 2nd Symphony for enlarged orchestra can have the proscenium stage floor flex on its perpendicular axis by over 1 1/2" on crescendos.. The visceral impact is enormous and very real. Headphones simply can't replicate that., but with good DAP's in-ear headphone are great for walk around portable use. I listen to Emotiv 5S ampified bookself speakers and a Yamaha subwoofer on my boat and like in-ear headphones more because speakers in a box always sound like speakers in a box unless inordinate sums are spent killing resonances. Too, balancing the subwoofer with those bookshelf units kills impact. So it goes . Head phones help.
I thought you said you were leaving?