I am pretty fast, been doing this over 20 years now and have always had a eye for quickness and efficiency. The toughest thing for me would just be letting go of some of the neatness and care.
You don't have to let go of any neatness. In fact, I think it's faster to do a neat job. Far less hassle and headache. Much more finesse, too. Smarter, not harder.
The biggest time/efficiency difference is in making sure all of one type of work is done before moving to the next (except for a few special items).
For instance, passing out boxes. Pass out all of them and don't miss any. Don't leave anything to have to come back to. Don't start nailing any of them until all the boxes are passed out
Then nailing up. Nail up everything. Don't miss anything. Don't drill even one hole until everything is nailed up. Don't leave anything to have to come back to.
Drilling holes. Drill all of them. Double check. Don't miss any. Don't leave any to have to come back to. Drill your pathways as efficiently as possible. This is a skill in its own, locating your pathways for maximum efficiency when pulling wire. 100% straight/level hole paths. No exceptions. Drilling around corners 100% lined up.
Pulling wire. No touching the whole wire. You only need your hands on the two feet on the end. Never, ever pull slack through a few holes, then pull that slack through more holes. That might be the biggest waste of time I've ever seen, aside from people who think they're saving time by making up as the go.
There are other of those "must do this" stuff that will set you apart in new construction (such as where to set up your wire for easiest pulling).
Believe me, I could put on a class about this, and most guys think I'm being overly anal. But these things will take a 70 hour rough-in and turn it into a 45 hour rough-in.
And it's just not something you can pop in and do. It takes practice. And patience. And determination.