Admiral Screed that's my main complaint about TNG and my main praise of Voyager. Voyager is a lot of fun and colorful, it's a romp. TNG is not a romp. Now some don't care for romps in their science fiction and that's fine.. for me I've watched and own all the series multiple times but Voyager is my crack candy.
It's also the most humorous Trek and I think TNG is the least humorous. TNG has little jests based on interactions (Data, Worf vs Humans) from time to time but that's about it. Voyager has the EMH's comic interchanges with everyone, Janeway's dry comments.. lots of wackiness. DS9 has the Ferengi and a lot of verbal sparring from Odo, Garak, Bashir. I do think Voyager takes itself the least seriously of all the Treks and it shows, there's quite a bit of fun in a lot of it.
Fun isn't a word I think of with TNG. I think it wanted to be science fiction and that's what it did.
Wot teh teacake
Although I suggest TNG failed to be science fiction. It was pretentious twaddle. I loved it at the time, but growing up and rewatching it has changed my opinion somewhat. By somewhat I mean completely.