I disagree. In much the way that some of the better DS9 episodes play like TNG-dark, some of the better VOY episodes play like TNG++, which is to say iteratively-improved-and/or-refined TNG.The Voyager episodes I really enjoyed were mostly Borg-related. I don't think it added anything special to the franchise beyond those.
"Prototype" comes to mind as an example of good TNG++, and that particular episode also suggests an analogous TOS++ style. B'Elanna is quite easily seen as the "Data" of the episode, and the robot proxy war of the big reveal is exactly the sort of thing that Kirk typically would have fixed were he not too late, as Janeway was.
Then there are straight-up great TNG-dark-style episodes like "The Thaw."
YMMV, of course.