Many people complain about Benjamin's personality change in the animated series but with a little thought, it makes sense. In the books, Benjamin is 9 and while he's quite competent and wiser than many of the adults the crew encounters, he's still quite young and therefore likely more coddled by his uncles and aunt (especially Doting Uncle Geronimo). Meanwhile, Benjamin is 12 in the show, meaning he's at the age where he's expected to do more for himself, so it's natural that he's not as clingy to Geronimo (no less admiring though). Besides, many people have their personalities change as they age, with only certain key traits (adoration of Geronimo and a keen mind being Benjamin's, in this case) staying constant.
In Valley of the Giant Skeletons, Geronimo twice states it took three days to do something, first saying it took that long for him, Thea, Benjamin and Trap to be driven to the titular desert and then taking another three days for the latter three to drive out for help. However, Geronimo never mentions anything like stopping for gas or getting hungry along the way. As such, it's more likely that the events didn't take three days, it just felt that way to Geronimo. Likewise, in Magical Mission, Geronimo claims that he stood in front of one of the lion statues for hours because it had come to life and started roaring insults at passerby. Like before, Geronimo never says anything about his paws getting cramped from standing there that long and it's more likely it was just a short while before something happened and it just felt like hours to Geronimo.
In the animated series' 26th episode, "Tea Story"; if the fernbiter is a mouse eating plant and it made all its way to Geronimo's office on the top floor of the Stilton Media Group's building, what happened to the rest of the employees?!
In the body swap episode of the animated series, Sally-as-Geronimo very deliberately locks Benjamin in a room to get him out of the way. Not only does he sound genuinely panicked as he begs to be let out, but at that point in the plot, he isn't aware of the switch, so one has to wonder what he thought was going on with his beloved uncle...
In A Fabumouse Vacation for Geronimo, Geronimo finds himself to vacate in the world's worst hotel, that looks very awful, is very expensive, and the local dishes are insect-based. After a while, he manages to still have fun by playing with kids in the hotel, discovers that the chef can also do cheese recipes, and stuff, and at the end he learns that you can find a nice side in everything and states it was the best holiday in his life... except that he still paid a gigantic load of money. (The hotel brochure is shown in a page, and you can see that they make you pay 20-30 more bucks per day just to do stuff like walking and breathing.)
