I agree with you but I would say that we are selecting developer instead of combat system.
For example there is no good reason to regroup Icewind Dale 2 that is based on the 3rd edition of D&D with Icewind Dale 1 and Planescape: Torment that is base one the 2nd edition like the Baldur’s Gates series (they differ a lot in matter of characters progression).
Also the combat system of DA2 is an excessively simplified version of the one of DAO and I would definitively not classify them together.
It would make much more sense to have the following categories:
- Baldur’s Gate 1, Baldur’s Gate, Icewind Dale 1 and Planescape: Torment (based on D&D 2nd edition)
- Icewind Dale 2, Neverinter Night 1 and Neverwinter Night 2 (based on D&D 3rd edition)
- Dragon Age Origins
- Dragon Age 2