Captain Jigglypuff
*On Vacation. Go Away!*
I agree. A smaller Dex is the best way to go and if there are a few more additions to the Pt Dex in BDSP, then I think these should be the additions other than the post game Legendaries and reasons why if any:I hate how big the regional Pokedex's have become since XY started the trend of having over 400+ Pokemon. In XY, SM, and SWSH with over 400+ Pokemon to choose from I feel overwhelmed can't decided which Pokemon I want to use throughout the whole playthrough.
Personally I prefer the regions with the smaller Pokedex of around 200 to 300.
Sylveon
Litwick line- Adds more Ghost and Fire type options
Darumaka line- Unovan for more Fire Types, Galarian found hidden post game near Snowpoint City via Poké Radar
Tynamo line- Adds more Electric types
Mr Rime- You get Galarian Mr Mime in place of the foreign Magikarp trade
Mimikyu- To continue being Pikachu’s rival and add lore that Mimikyu is more common than once thought but only recently started to be noticed more often in other regions
Ditto- To help with breeding and to get Phione