Memory attribute is pathetic. Allows one more slot per invested point. And… Well, that's it. All dialogue checks that have memory as an option also have checks on other attributes. Even worse in the game itself, a certain encounter gives "good" rewards only if you pass intelligence check, not memory (if it's even offered there, I forgot). Sure, you'll add a point or two in it so you can "memorize" enough moves/spells to use till cooldowns expire, but it generally feels like a waste.
Memory is pretty much mandatory for lone wolf characters though, as they tend to get a ton of skills. In my current run, I think I have mine at around 30 for both characters (meaning 10 points invested, as you start with 10 + get double points for being a lone wolf). I have close to two full bars of spells and skills now on both of them. It's getting pretty crazy, but they're also incredibly powerful, far more so than my previous, full party.
There are two dump stats though:
Constitution: Only need to get it high enough to use certain shields. Once your protections are gone, your only real way to survive is to get them back up again, or you'll face endless charm/stun/etc.
Wit: Only useful on one character, so that character can discover stuff + start the fight. The "initiative" system is unlike the D: OS1 system here in that it's more fair, so you get every other turn (unless it's a summon).