I went back and checked the first week sales for mothership titles (plus DotNW) that we still have media create records for. Symphonia GC and the earlier PS2 stuff seems to all be before this point.
Nintendo Platforms:
Wii
Dawn of the New World- 137k
Graces- 143k
DS
Innocence- 104k
Hearts- 140k (123k anime version, 17k cg version)
3DS
Abyss- 74k (late port)
Sony Platforms:
PS2
Symphonia- 265k (late port)
Rebirth- 335k
Legendia- 242k
Abyss- 405k
Destiny R- 270k (remake)
Destiny R DC- 117k (updated remake)
PS3
Vesperia 217k (late but expanded port)
Graces F- 215k (late but expanded port)
Symphonia Chronicles- 77k (remaster compilation)
Xillia- 525k
Xillia 2- 364k
Zesteria- 340k
Berseria- 76k (multiplat)
PS4
Zesteria- 5k (late port)
Berseria- 173k (multiplat)
PSP
Eternia- 81k (late port)
Destiny 2- 73k (late port)
Phantasia Full Voice Edition- 66k (late port)
Vita:
Innocence R- 55k (remake)
Hearts R- 55k (remake)
Playstation
home platforms have definitely been healthier for the series in Japan, but first week sales also look like they've been on a downswing since Xilia. Maybe there are other reasons for this of course, but they could end up reaching the same conclusion that NIS reached and realize that the console market is shrinking up enough to where one popular platform alone can't sustain them.