So Solasta was odd in that it diverted from the RAW 5e rules in that you could not change your spell slots without a long rest. In 5E you can do so outside of a long rest it just takes some time. This had the effect of making it so that you had to choose the identify spell slot in order to cast it as a ritual - so you are at least sacrificing a spell slot. Then the ritual takes 10 minutes per cast which they made happen in game time. That system works fine.
This is inaccurate. In 5e, you only have the opportunity to change which spells you have prepared after a long rest - and
then it takes some time. Solasta did this close to correctly (I don't think they have you spend the extra few minutes actually preparing - they just limit the opportunity to the end of long rests.
As for ritual casting, different classes interact with it differently. Clerics and Druids must have the spell prepared in order to ritual cast. Wizards only have to have it in their spellbook. Bards have to know the spell (they just know things or don't - there is no preparation). I don't think any other classes are able to cast as rituals. Anyway, Solasta did this correctly as well - wizards could ritual cast spells that were their spellbook that weren't memorized. I believe the clerics could only ritual cast spells that they had prepared (I didn't do any cleric ritual casting, so might be wrong here).
BG3 is in a different situation where ritual spells may not really work. Since you can switch spells at will but there is no time sacrifice for those changes. Then having a ritual spell would not have the same impact since spells slots can just be altered back and forth. On top of that there is no time mechanic where you can take x minutes to cast the ritual spell. You would just be creating a mechanic that may feel "out of place" or creates work for the sake of trying to make something fit. In essence you may as well make all ritual spells behave like cantrips (which they seem to do with Find Familiar) or you try to remove the need for the ritual spell (remove identify as a mechanic).
I am NOT saying either way is better. I am just pointing out that for BG3 ritual spells don't make a lot of sense.
The biggest reason that ritual spells don't really matter in BG3 is because you can long rest whenever you want with no consequences. The biggest benefit of casting a spell as a ritual is that you are preserving a spell slot in exchange for extra casting time. Since you don't really ritual cast during a battle (you can, but it's generally impractical) and you can get spell slots back whenever you want while not in battle, there's not really much point to having it in BG3 right now.
