Nice work, but need more improvement. Firstly, the edges to some kerbs are too sudden/sharp/steep. This causes the car to fly up into the sky and all over the place. I am quite sure that shouldn't happen in real life.
Secondly, I tested the track with the M3 GT2 and the track just felt too sticky, providing seemingly too much traction than any other tracks I had driven before in AC; doesn't seem like I can lose any traction.
Thirdly, there are unusual bumps in some places. Not too sure whether it's realistic. I will leave that to those who had driven on the real track to comment. But certainly, I didn't come across such bumps in other Suzuka tracks from other games or simulators like R3E.
Fourthly, there are not track markers? How then can we reference our braking point? Surely all tracks need some markers. As of now, there are not markers provided by the natural environment such as trees, neither are there man-made markers (i.e. those boards that tells you your distance away from the next corner as you are approaching it). Without this, I doubt I would drive on this track in the future.
Last but not least, the looks and feel of everything is just so unpolished and unfinished. Track surface, kerbs, grass, everything just looks cartoon-like. In its current state, I think the version should be 0.5 instead (i.e. this seems like only half the work done). So the 1 star given is to counteract all those 4/5 star "encouragement" reviews and bring things into perspective. Yes, you deserve to credit for all your hard work so far, but it's about time you work more on it rather than being satisfied with what you have done. Hence the 1 star serves as a reality check.
Good job so far, but the work is far from complete.