I will say this and not meant in a negative way at all. In fact, the opposite.
Getting where you are is impressive. But that lean that lean look isn't a good look at all. But it is an EXCELLENT place to go from, rather than trying to get buff from being a fat dude and pinning gear thinking you are going to "recomp" to an appealing physique.
Hell, most of the local bodybuilding shows never showcase anyone that gets that lean.
I wish I could have gotten all of my clients a fraction of that lean before they started using gear. But that just rarely happened. Rarely did they have the patience, drive and foresight to stick with anything the way it is obvious that you have.
So good on ya' and now, following your obviously competent coach's guidance, put on that muscle you really are wanting.