Doesn't look like there's much incoming until the second half of November, but then in 3 weeks pretty much everything comes at once: Animal Crossing Amiibo Festival, Taiko Drum, Yokai Watch Dance, Mario Tennis Ultra Smash (no exact date yet afaik, though), and possibly Disney Infinty 3.0 and Harvest Moon: Seeds of Memory (both are slated Q4 2015 in Japan). And than of course Genei Ibunroku #FE at the end of the year to finish on a high note.
On the other hand, with that baseline, even some lower percentage boosts should have a big effect on the overall sales. Considering everything is clustered around 3 weeks in end November/early December, the sales shouldn't drop out in between the weeks and could have great sales in the end. The question is will this be enough to beat 2013 or not?
In the end, what possibly saves 2013 from being overtaken by 2015 is imo not so much it's big end holiday season boost, but more it's head start it had early this year. 2015 had a 120k gap to close first over this whole spring and summer and it's already a great feat that the Wii U this year managed to close that gap and overtake 2013 before the holiday season, but if will be hard to boost even more to stay up front in the end.
On another note, if NX doesn't come out next year (which I doubt btw), I think 2016 has a good shot to become the best selling year for Wii U in Japan. The increased baseline and the boosted start (leftover from Ginei Ibunroku #FE) into next year should avoid the problems the console had this winter and spring and with some heavy hitters should enjoy a very good year and holiday season