There only being a level 2 Trunks in video games up until now isn't exactly an inconsistency though, I mean he wasn't going to go level 2 in the arc where he originally appeared, because that was kind of how Gohan became the hero of the whole thing and saved everyone by beating Cell. He's been gone now for years and years and years, so it's perfectly acceptable to believe in that time he figured out how to at least go level 2 - I mean, his younger self in this dimension figured it out even quicker than that. If it annoyed you that they made it up years earlier in video games, well yeah, that kind of shit is annoying - because it's not canon. My entire argument.
And as far as Super Saiyan 2 Trunks taking the blow from someone way out of his level was something they mentioned on the side in the manga, but I don't believe it made it into the anime, which kinda irked me because it's sort of important.
In the manga, at least, when Trunks first got back and originally showed Goku what he could do, he powered up to level 2, and Vegeta made the comment that Trunks' Level 2 was at a power level stronger than Goku's Level 3, and Trunks made some snarky comment about how he powered up over the years but never bothered with the whole transformation side of it. So while in the anime didn't make much sense it did at least have some sort of a base of explanation from the original source, albeit not included.
I mean, I get what you're saying, but it's never really seemed THAT inconsistent at times. Annoying with all the power ups, and keeping track of shit like that but for the most part i'd like to think it makes sense and everything has an explanation. I've seen much, much, much, much worse inconsistencies in other animes/mangas.
