Part of the problem is an overall feeling watching these episodes:
"Things just aren't the same anymore."
That's nobody's fault. The writers had to move forward regarding some storylines.
1) Jock's death had triggered many events, and those events moved pretty quickly. Now is when we see for the first time a day to day routine at Southfork without Jock. It's the first time of everybody wondering, "What now?"
2) Clayton moves to Southfork. As a Howard Keel fan, I'm glad to see him. But this changes the whole dynamic at Southfork.
3) Many new characters are now part of the main plot. Jaimie, Jenna, Charlie, Naldo. Dallas is totally different.
It's easy to watch this season with a bit of disappointment, thinking that things just aren't the same on our favorite Friday nights. Donna Reed is just the most obvious example of that, which is not her fault.