So, why is Beroba still around? She interrupted a previous DGP, attempted to kill Riders, DGP Staff, and harm other sponsors, stole DGP equipment, and openly stated how she just wants to cause harm. She is no longer in control of the GP, and seems to just be demoted to a sponsor, why on earth is there not a single Rider or DGP member that, you know, wants to at least remove her from the current DGP?

Also sad to see Archimendal go, though I don't even know why he was kept around so long. Funnier still that he got a character song with the rest of the Jyamato Affialiates only to be unceremoniously killed of right after. Legiel and the Chameleon Deadman's death felt like it had more impact than Archimendal at this point

There's actually a simple answer to that.
Who can find her? When she was running the JGP, where she was out in the open the most, she was still incredibly illusive to the point where she was only encountered when she made a move first. Now that she's hiding in the shadows, it seems the only one know reliably knows where she is, is Kekera.

Maybe JGP had big audience ratings? Well, Niram even seemed to enjoy the risk to his life, although he does not have that much of an extensive emotional range.

True, although to be fair I'm not sure why Kekera is helping her, given that he only teamed up with her to bring Keiwa back when she ran the JGP, but now isn't in charge on anything.

Maybe I missed this, but was there ever an explanation given for why none of the DGP, the lower level staff, and/or sponsors have even brought up the time travel aspect as an option? I don't recall anyone ever saying "How about we go to the near future to see how this turns out, and then go back to the past to prevent X event from happening." Sueru mentioned that once they are done with this period of time they can just leave "as if nothing ever happened" which can't be entirely true given that Ace's wishes had long last impacts throughout the ages.

What if the time for the DGP seasons was not chosen in chronological order? I mean, Niram mentioned Ancient Rome and Sengoku, but Ace was in at least two more. My point is that there may be DGPs that are past for Ace's but not for DGP staff. Or is it too complicated a concept for a children's show?
Also, judging by the gates, I would venture to suggest that time travel in Geats is much more difficult and energy-intensive than in Den-O and Zi-O, and it?s impossible to just hit the road half a year into the future.

That's true, although the DGP's Ace has participated in the past have to be in the past for the current DGP as well, or Giriori wouldn't have the past wishes of Ace, unless they were given to him from the future, in which case they could have decided in the present to not choose the original version of the original Ace from the past, if that makes sense

I was referring to the DGPs that Ace has participated in in past lives.