One of the principles of dramatic writing is to keep a good pace.
When you get to slow spots, speed up. Nobody needs a thirty-page travel sequence if the only thing that happens is “they get there.”
When you get to fast spots, slow down. Describe the smell of combat and the taste of blood.
No matter what you decide to do in terms of narrative pacing, be aware of it. Slow spots are awesome, especially if your players use those times to flesh out their characters. Fast-paced action sequences are great, too, especially if you use them to increase the tension at the table.
Speed up, slow down … and do it on purpose.
Now get out there and tell a story (and if you need one to tell, check out my work on DMsGuild)!