Atlus has ramped up Persona series because of sales both in Japan and US. They are likely moving to make Persona a flagship series. Whether that is good or bad has yet to be seen (could be bad as sometimes flagship series tend to get watered down to suit bigger audience).
However it’s been my belief, and continues to be, that if Japanese game companies want to make inrodes into dating sim games that are more lucrative in Japan, then they will have to do stuff like this (or stuff like Ilussion, but better…and that’s only for the ero market). Dating sims themselves won’t sell, especially when they are Americanized. Companies lose out on those who might buy it for its anime graphics and they can’t get enough people interested to make up for that loss.
Persona 3 has shown that you can have a dating simulation are a core feature of a game and make it sell (in fact arguably increase it sales) in the western (particuarly the North American) market, so long as you’re willing to do so as part of a larger game mechanism, in this case an rpg (and thus because of the copycat syndrome any future stuff will likely be similar merger for foreseeable future as it will be seen as less risky).
Also:
PS1’s Azure Dreams: Another Life
GBC’s Azure Dream (a stripped down, but easier and more stable remake)
Rune Factory Series (more rpgish than HM)
Phantasy Star 3 (i believe…)
PSP: Star Ocean: First Depature (just released this week)
PS2: Star Ocean: Till the End of Time (though not so much as previous games)