So, I just rewatched Bugs. Consistently considered one of the 'worst' episodes. Even heard TPTB name it a fail. Gotta disagree to a point. Plot is dumbass silly. True.
But ... consider what the episode does give us.
1. First time (I think) boys are considered a 'couple'. Dean jokingly calls Sam 'honey' and slaps him on the butt.
2. The Impala is in every scene. Thing of beauty. And Sam is driving a lot in this one. Continuity from previous episodes, which is nice. So lots of unusual Sam driving.
3. A ton of brother moments. Ongoing Sam whining about how they were raised. Defensive Dean. Everything not said shown on their expressive faces. Sam opening up re his leaving for college, needing to get away. Dean never saying it directly but clear as hell how it hurt them all. Canon admission that John (and most likely also Dean although not stated outright) checked up on Sam in Stanford -- a lot. Fun bantering at first and honest emotions in the end. And really beautiful and understated performances by both Jensen and Jared.
4. Bees. We've heard a lot from both actors about how not fun those scenes were. They looked pretty horrific. Made me itchy just watching it.
5. Kim Manners directed. Beautiful closeups of both actors. As a director Manners knew what he was working with and let the boys shine.
So, not a waste of time to rewatch at all. Progressed the backstory, progressed the 'search for Dad' story. Some lovely lines, like Dean saying at the end that they'll find Dad and Sam will apologize and then they'll be at it again in no time. So true.
Other, somewhat shallow things to point out.
-- Dean wearing jewelry. Ring, bracelets, amulet.
-- Dean wearing leather jacket. (Man, I miss that jacket.)
-- Sammy's bangs. Can't say I miss them. But he was so cute.
-- Both their voices. Higher, softer, younger. Again, it's not something to miss necessarily. But it's fun to listen to them that way.
Finally, this episode showcases how much each character has grown and changed. Reminds me how exceptional the Show is in this regard. How amazing those characters are and how far the creative team has taken them.