After playing this game for some time I think it has become one of the games that I've had the most fun playing in general.
The mix of combat, management/breeding,, being able to tune the units until they're exactly how I want them to be with specific roles in a team, and finding combos and synergies to become even more powerful is amazing. I've also enjoyed the exploration even though I don't know if that's a main draw for me in video games.
But maybe this is all thanks to how many of the core systems and mechanics of the game are very polished and developed, specifically things like combat, exploration, breeding, and fusion; all of these things feel like they support one another directly or indirectly, but also each of them just flows very well on their own which at least for me has provided an experience where I've felt like with enough preparation or coming up with an unexpected solution to a problem I can actually find success against the challenges I encounter.
This game is very entertaining to me, with seemingly most options for teams that can be built being viable even for late-game as long as said team is optimized, so it feels like if I can imagine a certain combo I want to use chances are not only would it be possible to actually make it work, but it could even be optimized into being actually good or even great for winning fights.
So basically, I think this game has quite a lot of great things, the core mechanics have been developed to an excellent degree where, at least I feel like the main gameplay loop is one where the player can plan how they want to succeed in their own way, and then they can find what they need to achieve that, even if it's challenging.
It's because of all these things that I think Portals of Phereon is a great game.
Edit: I think maybe I should mention a few more things. I focused only on the positives of this game, which I do think it has many, but I left out some things that maybe a new player should be aware of:
Despite all the things this game does very well, it has certain flaws, and in particular the many different systems and options available from the very start can be overwhelming and confusing for someone that doesn't already know how everything works.
On my first playthrough I felt overwhelmed and, in particular with the dating minigame, I became increasingly frustrated as I didn't understand things like what each number meant or what the difference was between cards and events, even after trying to read the tooltip from the question mark in the corner. It was only after reading the wiki page about the minigame that I started to understand and could actually make progress.
There were many other systems that seemed daunting for me to approach and I ended up not interacting much with them throughout my first playthrough. But as I've continued to play I have started to try some of these other systems and I think now I understand how they work.
But anyway, I've ultimately really liked the game and the more I understood the better the game felt to play because now I can just interact with any system at my own pace since now I know what each system can provide, whether its resources, units, items, etc., so I can focus on what I require in the moment.
I do believe that the game is very fun, at least to me, perhaps mostly because of how well made its most essential systems and mechanics are and how they support each other. And I think maybe that makes me feel like a 5 star review is fair for how great of an experience the game has provided me, even if at the start it was a lot of struggle because I didn't know how the game worked.