Thread summary:
OP: Is TOS over-rated? I found it dramatically stretched at points.
(8 pages later) Well, YOU obviously don't understand the Prime Directive!!
(20 pages later) What about the moral implications of Metaphasic Radiation then?!
Ok, I skimmed over all that stuff.
Despite being a huge TOS fan, the OP has a somewhat valid point. TOS episodes are built around one big dramatic conflict that requires extraordinary decisions from the main characters. However if you aren't "hooked" by the drama, then the episodes can be predictable and flat.
On the other hand, TNG often had episodes based around very insignificant personal matters. (And then X learned a valuable lesson...) In the context of the whole series, these episodes built up the characters for the big dramatic finales. But as standalone shows they often seemed plodding and pointless.
People treat Star Trek like library material nowdays. Rather than sitting down and powering through a bunch of episodes, ask yourself if you would make special plans to stay home and watch it. On that count, TOS wins overall IMO.