This reminds me more of a design between the 2360s and 2370s based on the Excelsior-class. This could well be a second Excelsior that bears said name, but not necessarily first in her class or a refit. I'm mostly basing this on the preservation of the Excelsior-class while beautifully-incorporating designs from other class of ships, if only one or two others though. The nacelles are unique but you can say they're somewhat of an "upgrade" of nacelles from, say, the Cheyenne-class as I'm half-reminded of. I'm also partially-reminded of the Akira-class's engines, albeit less Galaxy-class-ish and smaller. I'd say it's probably a 2360s ship, if TNG-era. Overall a nice design, and I think it has potential to be a TNG ship that can have a variant or two, like a carrier as suggested, for example.
So basically I'm expressing thoughts out loud whilst praising. *shrug* Good work.