The MINIATURE fx from the first few seasons don't hold up well,
They look like 1985 TZ eps, which for me is worse than most TOS fx in lighting and presence.
What are TZ eps? Do you have a Memory Alpha URL link?
By the way I was just watching the special features on season 4's last disc and I checked out the last 2 episodes and man
are they unsharp! They just do not compare to Voyager
which was only 5 years later and that is due to the telecine used at the time of production and if it were telecined to digital tape in 1990-91. As far as I know they used D2 video format to master to.