Video discussing my thoughts in more detail here:
October looks like it's going to be an exciting month. Nothing ground-breaking, but everything is a welcome and interesting update. Top mentions are:
KBD: Old boss revamps are always bound to revive dead content, especially something as old as the KBD which literally has not been exclusively touched in years. Should boost both QBD and KBD popularity with the ornament kit drop. Finally, I am really looking forward to the new lore introduced. I'll probably go out and kill KBD a few times (if possible granted the high accessibility and low difficulty of the KBD) just to find out about it first hand.
H'ween Event: I forgot to mention in the video, but I do believe this year's holiday event is the first event where Jagex is offering rewards beyond typical cosmetic items in the form of the ecto-whatever-crusher. It's not a significant item, as the bonecrusher itself isn't very big, but it should be a nice little thing to have. Not really anything else special, although Jagex also seems to be going away from the Grim Reaper theme of Halloween and overall making less of a big deal about this seasonal event. May just be because there's two this month. Eh.
Solomon's Store: Not all worthy mentions are good ones. I could rant on about the increased emphasis on clearly unpopular microtransactions, but instead I'll comment on how Jagex is focusing increasingly on their latest microtransaction method. Notice the progression from loyalty store -> SoF -> Solomon's, and how they've slowly put more weight on the newer one while easing off the older ones.