I'm sorry, but I still think that Ahsoka's continued presence is because she is a damn good character that has been well written with a true character arc both her creator refusing to let go of his brain child and Disney's refusal to let go of a cash cow...she should have been killed by Vader in Rebels, it further cements him as a tragic figure and her purpose as a character was complete.
Time travel...I mean...COME ON. The problem with the plethora of animated cartoon mediums is that we keep straying further and further into comic book super hero land. Time traveling Jedi, lightspeed trips taking a matter of seconds (when R2 flies all the way to Coruscant to get Anakin and Mace help), a dude being cut in half HIGH UP somehow surviving without replacing half of his internal organs (Maul). I'm afraid of how ridiculous it's going to keep getting.
For an order that was hunted down and destroyed to the brink of extinction, more and more Jedi keep popping up as survivors in recent years.