In the real world, a fight between two equal adversaries would be almost unheard of. Surely both sides would want to engage only from a position of strength?
Out of the Trek films, ST2:TWoK already dealt with the rare scenario where clever commanding settles an even match. ST:TMP and ST4:TVH show how an uneven battle can be won by the underdog, again going for the realistic approach, namely not agreeing to fight. ST:GEN is a fun exercise in how the top dog can lose, and overall enjoyable since heroes seldom are allowed to be defeated. ST3:TSfS shows two masters of bluff playing a merciless game with laughably weak hands, focusing the attention from the hardware to the people involved. That's plenty of nice diversity there...
...Meaning I wouldn't really have minded
a rematch with even ships, even though it has already been done. It's true that Kirk has never faced an alien foe that was evenly matched - essentially, a Klingon battle cruiser that doesn't get in a sucker punch or a saboteur or some other dirty trick first - in an open fight, but it shouldn't be too difficult to think of a plot where he's forced to do such a tactically inadvisable thing.