Well, I finished this game!
Kudos for the graphics - the gigantic resolution 1280x1204 is interesting, I pressed the "F" key and nothing happened ^_^. Since my screen resolution is also 1280x1204 - it took me a few seconds to realize what was going on - I wonder why this resolution was chosen though.
Anyway, the combination of vectorized photography and non-textured 3D models seemed a bit sterile at first, but it remained constant for the whole of the game, and gave it a good sense of atmosphere, and even though it took a pinch more imagination than games with full-scale graphics, after 20 minutes, at least for me, the illusion was there. Really excellent - except for that disco... I played at night, with only the monitor's glow, and I thought I would get that Pokemon fit or if I'm lucky that only some veins in my eyes explode. It was really hard to read, I covered the screen with my hand, trying to have only the textbox in view, but it still hurt.
The voices and narration was nice as well - as I said before, the foreign students could have used more accents, but it was nothing that would bother me that much. I liked Nakamura's squeaky voice... though that seemed rather Chinese-ish, than Japanese-ish. Nevertheless, I was impressed by the scale of the voice acting - there was really a lot of time put into that, the voices were crisp and I assume this was all very well prepared.
But to get to the point - the story and overall atmosphere - it really continued with the first impression it gave me - this was like a travelogue you could experience yourself. It made a very good effort in being close to reality - I've never climbed the Fujisan, but I really felt like it was realistic what happened in the VN and the climax of that part was really touching - I almost thought there would be a reference to the rising sun on the Japanese flag. There were several good touches like this scattered all over the VN even though some felt a bit educational. And of course as with every good thing, there are some things that you could nitpick - such as that Felix claims to have 8 semesters in japanology and then Yui has to explain to him what the suffix -chan means.
I guess this is all from the need to balance the information with the competence - you generally don't want a patronizing "this is how they do it in Japan" story, on the other hand going into too much detail with discussions about something too specific is also alienating - so I found the balance very nice - and I learned a thing or two as well. As for the cliches, I think the game handles them well, there was nothing standing out too much, and having no cliches would be disappointing - and again, I think the balance was good.
Overall, I really enjoyed it - though this wasn't the first German VN I played (there was Honey Hotel, which was done by AFAIK what Austrians like to call "South-Tyroleans", but whether you can call the beach cliches with sexy girls a VN is another matter - well, for me you can - but that's another matter entirely

Anyway, as far as the story goes, it's - how should I say - neutral, I think is the word. It fits the nature of the project and I wouldn't expect any other resolution to the conflicts or any other things that Felix comes to understand or realize at the end. One remark (not a bad one, just a note) to this is that this all contributes to the project feeling academic, in adition to being artistic. And as such, it's quite realistic in that it shows the typical way that an exchange year usually takes. Combined with the numerous small episodes and attention to detail, this is really a nice (and since this is still somewhat special in OELVN) also a very polished work.
Congratulations!