>>26591420>1 Pokemon Caught>3 Pokemon SeenFirst, this implies that you do get to register the 3rd starter that you or your rival don't pick. Either because Lillie takes it or because you "see" it. Other games didn't give you that choice, so something nice to add.
Anyway, some math:
>Assuming the 1% is total Pokemon seen (which is the more likely option as Gen 6 followed this as the more important statistic versus Pokemon caught)100% - 1% = 99% Pokemon NOT seen
1% = 3 Pokemon seen
So 3 x 99 = 297 more Pokemon left to see
297 + 3 = 300 total Pokemon in Dex
This not only works as a viable number for the regional dex, but if it's truly split 4 ways (1 for each island) we can expect somewhere around 75 Pokemon per island (if they go for balance).
Doubtful they will give us 300 NEW Pokemon, and we KNOW there are old Pokemon. No idea how many new mons there are, but we should be expecting 300 TOTAL before the National Dex