Woah, woah. First of all, the eroge was released after the all ages version. Plus, if you haven't finished the VN, there is absolutely no way you could judge it because all the epic stuff happens in the last arc, Refrain.
I will judge it, because even if it does have one amazing arc, the fact you can't see it at all until you've played through
every single other arc in the game, many of which (ie. the three I finished before giving up) were crap, and which would take tens or even hundreds of hours, means that it is not a good game. I'll take your word for it that refrain's good, but there's no way in hell I'm slogging through all the rest of the game in order to find out.
IMO, Little Busters had two main good points: The batting practice minigame (no idea why, but I really loved it), which obviously can't be in an anime, and Key's usual quirky humour, which I quite like. Sadly, unlike previous Key anime adaptations, this one has done a really bad job of adapting the jokes to an anime, and the humour that JC Staff have added themselves is mostly pretty weak. It feels like very generic stereotypical anime humour, which just isn't funny.
I think people need to grow some patience and not expect everything to be thrown at them in the first 3 episodes. I've read comments by VN players who stated to have played this game for 50+ hours. If each arc starts in pretty much the same way, and a lot of the good stuff doesn't come till way later, why can people sit through that and not get bored, yet can't sit through an anime that condenses all these storylines into one, and is much, much shorter (including any season that may come after it), relatively speaking?
And even those that haven't played the game, and watched stuff like Clannad (which also took a full season to have anything of significance happen, but where each of the girls' stories had some connection to the overall plot), why is anyone surprised that the LB anime takes such a long time to get really serious?
I can't speak for anyone else, but I only got through as many routes as I did because I discovered that if I held down the skip button then clicked out of the VM I was playing it in, it would keep skipping through all the repeated stuff while I went off and did something more interesting instead. I just had to check back every now and then to make choices, until it got to new material.