I read ENT fan fic (tho I read TNG novels as well as the ENT ones, so maybe I'll give some of those TNG suggestions a look-see) and my fave, all time wonderful fan fic is "Cry Havoc" by Missanthropic at Hot (House of Tucker)
Link: Cry Havoc
It's listed as NC-17, but only Chapter 15 can be rated as such. It's a fantastic story, but it's also 'shippy towards Trip and T'Pol, so take that as you will. It takes place during the third season (in the Expanse) and introduces some new characters, and a new ship. It's long, but I read it in one sitting, 'cos I just couldn't stop!