Hey, it only took me like a year and a half, but I finally finished all of Eternal Poison! Opinion didn't really change, but obviously I liked it enough to go through all 5 paths. Heaps of a potential with a lot of glaring flaws; lots of style, but the lack of polish on the battle system is unforgivable because it would be so easily implemented (Also serves as a good way to never have VP:DS lack of numbers be rendered completely inoffensive). That said, I'm sure that they ran out of money (Certainly seems like each plot thread had several parts that they just didn't have time to write. Ashley's path was especially glaring here).
Final battle and spoiler chapter were cute if only because they somehow made summoning actually have a purpose (Less cute was the slog part, but at least they boss did have a scary attack). Was disappointed in the ending, but I had heard that in the end Thage was supposed to destroy the world or say that everyone played into her master plot or something.
Just for fun, in game rankings off the top of my head. Some of these of course are seriously foggy since it was a year ago.
Thage: 8.5. MVP. Smashes shit up, and is hard to damage. Little bit docked because if someone can damage or status her, you're depending on items to heal.
Raki: 5.5. Eh. I guess not needing to equip 7 is a small bonus. Didn't feel as good at anything as you'd expect.
Retica: 7. Bows+Healing.
Ashley: 8. Great healer, surprisingly good at attacking.
Reyna: 6. Starts off really solid, but she's the only character in game who basically starts off at core competency (Gains no weapon or skillset worth anything really).
Glynne: 4.5. Holy crap, single damage type? Yeah, he has magic, but really can't make much use of it. Reyna has the same damage type with far superior range.
Olifen: 7. Only hero to feel overall outclassed by other special PCs.
Logue: 5
Marie: 7.5. The smashing.
Levatte: 7.5. Heals forever, ton of buffs for leveling.
Rondeminion: 7.5. Crushes things absurdly, but don't expect anything at all outside of melee range.
Duphaston: 5. Eh. Surprisingly lackluster. Can do a bit of everything, but nothing well at all (MT is kind of bad, Healing is mehish)
Alexei: 4. Gets a point just because if you drag him around long often in the right chapters, that 100% Fracture will be awesome at taking down some bosses.
Ares: 4.5. Okay fighter. Gets spears, is fast, and is lackluster. Competent enough though and fills a few holes that may be needed.
Irina: 6.5. Retica minus. Bow users are always a solid choice.
Velnor: 6.5. Range+Accelero. Bow users are always a solid choice.
Komori: 7. Best Merc? Only one I used in every chapter. Buffs for leveling, early healing, passable magic, solid physicals of two types.
Vivian: 6. Doesn't have the range of skillsets Komori has, but the damage is pretty great. 3 of 4, I believe.
Yuri: 6.5. Indispensable on 2 of 4 paths, but Levatte and Ashley make her a bit irrelevant. Better usage than Komori on Thage/Rondeminion.
Stein: 5.5. Solid magic, eventually gets Cure 2. Does need some levels, but he's not...
Nena: 1.5. Horrible everything. Speed is trash, HP is trash, damage is lowest for mages I think, she has no healing, no buffing. Her niche is...late kind of crappy MT damage? Her whole score is derived for potentially being a warm body early, but she's auto dropped whenever the 7th PC comes along.