I've really liked this past season, but yeah it doesn't feel like its hitting the highs of season 4 for me which was all killer no filler. Hell the best episode was a "filler" episode with Fitz and Simmons. It just feels different this season.
"Longest running Marvel series to date"
Is it even a contest? Has any other show even made it beyond a third season?
The former two aren't even close to SHIELD in pure runtime per season even - even if each episode of the Netflix shows were a little longer than a standard television hour, it's still 22 episodes against 13 episode seasons.Nope. Daredevil, Jessica Jones, and Legion are all tied at 3 seasons each.
You're missing out. A lot of people consider seasons 2 and 4 to be some of the best stuff Marvel has to offer.