Unlike all the sexploitation in Trek, from Theiss wear to catsuits, "A Night in Sickbay" was actually ABOUT sex.
The episode was a bit over the top like Trouble with Tribbles but I fail to see why this should be a problem. Both episodes are definitely better than "standard meal" Trek (and TOS as well as ENT and all other series had ample of that).
For me, it is because it comes out of nowhere and goes nowhere. The sexual tension is not saying that was ever really discussed before, and is brought up because Phlox decides to discuss it with Archer while Porthos needs critical surgery. No, that doesn't follow for me, either from character's personality or arcs at the time.
In addition, the central crisis comes about from Archer's failure as a diplomat, and that does not engender sympathy in a meaningful way from me.
"Comes out of nowhere and goes nowhere" is true for all non-serialized Trek stories. Take Picard#s seond life, it should have had a tremendous impact upon him but in the next episode it is ignored for obvious reasons.
There is nothing wrong with preferring slightly theatrical (emaing nor realistic, larger than life) captains like Kirk and Picard. The latter is by far my favourite Trek character. But I tremendously enjoyed to see Archer mess up in two respect in "A Night in Sickbay". It is also perfect in synch with the character, Archer is the first captain out there who messes up and learns hard lessons.
Here it might be on the funny side but so what, Trek doesn't always have to be deas serious.