Okay, something's starting to confuse me, why didn't King Drasil just send Omnimon? He's seen at the end and in the opening, and he's arguably one of the most powerful Digimon in the entire franchise, so why didn't King Drasil send his strongest to attack the humans who he knows have stood up to very powerful Digimon? One of which is a freaking Demon Lord, the fuck!?
What bugs me is that Thomas didn't tell anybody that he was going to pretend to work for Kurata, which led to a fight with Marcus that got taken to such a far extreme that Agumon ended up being reverted to a Digiegg, which would wipe Agumon's memory completely. So, basically, for all he knew, Thomas had Gaomon kill Agumon. Murder. What the Hell, Thomas? Retroactively ruined what was otherwise a very cool fight, in my opinion.
Thomas didn't have Mirage Gaogamon kill Agumon. Mirage Gaogamon was purposefully pulling his punches when fighting with the other DATS members (Ikuto and Gaomon explicitly say this later). What killed Agumon was Masaru freaking the hell out using a power Thomas wasn't aware existed. He couldn't tell Masaru because well - Masaru would screw up his plan. But it was kind of not cool he didn't tell any of the others.
Why does Keenan talk in the typical "neanderthal" speech in the dub when he was raised by Digimon that spoke perfect English?
There are monsters in the Digital World who don't speak at all, so they were probably content with being able to understand Keenan. Furthermore, he's ten. Some kids will start speaking in strange grammar structure to make themselves sound more unique. In the real world, parents and teachers would probably correct that before caveman speak became too much of a habit but the Digimon likely didn't care because again, many of them don't speak at all.
Also, aside from Falcomon, his other friends were a Bubbmon, Motimon, and an Otamamon. Two infants and a Digimon known for being an idiot. We never hear them talk, but I bet he picked it up from them.
The answer is that the dub was simply translating the bad grammar in the original japanese.
There is something that really bugs me. Why were the humans not told that the Digital World existed? Sure, something like the DATS would be necessary if a criminal or the like wanted to use a Digimon for his or her own purposes. But I can't find a reason to keep the Digital World secret from everyone not in the government / the DATS.
Take one look at Kurata and tell me if that's such a good idea. It was established that not everyone is ready to handle the idea of Digimon or digial world.
Perhaps it's established better later on, but why does Thomas outclass Marcus so much during their boxing match when they first meet. Marcus doesn't have the tactical skills, but he is still a highly accomplished street fighter. He took out a dozen guys by himself and fought Agumon for hours; this is besides the fact that he straight out punches Champion-level Digimon on a comparable strength level. Thomas' style is to order Gaomon, so he should be on par with Marcus at best.
He is on par with Marcus. During the fight, Marcus was being cocky and understimated Thomas, allowing him to connect the first punch and knocking him down enough time to "win" the match (it's later shown Thomas is a boxing fan, and practices it regularly).
Is it just me, or does the theme song sound a lot more like a Pokemon theme song?