There is a new series called TodHunter Moon. Have you heard of it? It's not as good as Septimus Heap, but it's nice if you want to see how the characters all grew up.
Oh, and Beetle's another favorite of mine!! He's such an adorable character :D

Haven't heard of it, what is it about?

Another ave would be Marcellus Pye and his awesome alchemy tricks.

It's a a sequel series to Septimus Heap. Ummm...I'm really horrible at giving plots without it being too long and incoherent, so here's the official synopsis:
When Alice TodHunter Moon—who insists on being called Tod—was five years old, she saw a beautiful golden dragon boat fly over her PathFinder village. She knew at once that the boat was Magykal.

That was years ago, before her mother died, her father disappeared at sea, and the Garmin took her best friend, Ferdie.

Now it’s up to Tod and Ferdie’s brother Oskar to rescue Ferdie from the Garmins’ keeper, the malevolent Lady. Their journey takes them to the Castle, where they receive help from ExtraOrdinary Wizard Septimus Heap and Ex-ExtraOrdinary Wizard Marcia Overstrand.

But the Lady’s brother, the Darke Sorcerer Oraton-Marr, has a plan that will put everyone Tod holds dear in danger. To save her people, Tod must embrace her identity as a PathFinder and navigate the Ancient Ways—mysterious Magykal paths leading to unfamiliar—and sometimes dangerous—lands.

Taking place seven years (get it, seven? ;) ) after the story arc of the original bestselling Septimus Heap series, and full of Angie Sage’s characteristic humor and heart, PathFinder celebrates the joy of discovering one’s own personal Magyk, and of choosing the path that lets that Magyk flourish and grow.
Do you want spoilers?
I wasn't really that interested in the actual plot; I was more interested in seeing how the old characters had grown up and were getting on with their lives.
Marcellus is hilarious!!! I totally ship him and Marcia! I've got a spoiler for that too, if you'd like... ;)

Hm, sounds interesting... I'll add it to my list and read it when I have time, so sometimes in the next ten years I'll get back to you :p

As for spoilers, just teeeensy ones maybe, like yeah, Marcie and Marcie do they get together or are they still pretending to hate each other?

NOOOO!!! They don't!!!! That's what I hate about it so much!!! She marries Milo, of all people. I mean, I could sort of tell from the previous books, especially Fyre, but..I don't like it (stomps like an angry toddler).
On the bright side, though, Marcia's basically married herself into the Heap family :) . She's officially Sep's "mom" now. And Jenna now has a biological mom, a foster mom, and a stepmom. Pretty cool :D