Forget the binary between duration and seasonality; what really matters is adaptability and preparation.
Reducing the trip to two weeks for budget reasons in low season does not guarantee the best experience if you expect high-season activities.
An off-the-beaten-path approach involves accepting that low season offers different and often more authentic beauties.
For example, visiting Kyoto temples under snow in January is an unforgettable experience and often less costly, even for a short stay, because the atmosphere and photographic opportunities are unique, far from usual crowds.