Its definitely interesting, but G5 is by far the hardest of the series. I've beat G1-G4 on torment, and only G4 was moderately difficult (I do a bit of powergaming and read the FAQs, so it does reduce the difficulty somewhat). G5 constantly throws lethal situations at you, and theres a lot of content that generally needs skipping until you're stronger, or severe abuse of the combat system to power through. I'm stymied by the number of regular enemies (rats, worms!) that have 10-12 AP and can punch a hole through your team. Acid is far more lethal on G5 than previous games, and aura effects just feel incredibly unfair on torment (unbound for example). G5 Torment truly feels like the game is imbalanced, and it is expected that you are both an experienced Geneforge player and also powergaming or consulting a guide to relatively maximize your character power. My shaper is level 40, just about to enter Dera and yet I constantly need to be pre-buffed before fights if I want to survive.
However, I do think that the leadership and mechanics of G5 is way more forgiving and the checks are easier to pass than prior games. There is also a tremendous amount of exp on the map, which opens up possibilities for long term creations that you roll throughout endgame. That being said, it could be a hassle to try to get a cryoa to level 50 due to the lack of resistances.