The "cheesy" criticism has always irked me. I also get really frustrated when I even read professional reviewers/columnists who dismiss TOS with its "cardboard sets" and "ships on strings".
TOS represented state of the art "technique" for set design and optical effects. The only difference between a TOS visual and, say, a visual from "2001" is not the technique but the amount of time and money they could spend.
TOS FX were mostly wooden models in on some kind of stand, in front of blue-screen, with backgrounds optically matted in. Exotic backgrounds were beautiful matte paintings, and sets were primarily painted plywood over 2X4 frames, with electrical wiring to make it look "powered".
All the big budget SF movies of from the 50s all the way to the 80s used this exact same technology(admittedly, SW bumped it up a notch with computerized motion control, but that didn't happen until 10 years after TOS).
Again, the only difference was time and money. If the TOS producers could have spent the money, and had the time, TOS FX would have looked as good as 2001.
There was no cardboard, no ships on fishing wire, etc etc.
The visual aesthetic represented an artistic choice by the various filmakers involved, informed by the styles of the times.
It's interesting, that 20 years after TNG, they are often criticized for being bland.
I guess it's all a matter of opinion. I just wish so called "professionals" were careful enough to do the research before they make such statements in columns and reviews, that might actually affect someone's choice who hasn't seen for themself yet.
Sorry for the rant, this one just gets under my skin....