Rather too many people here getting frothy over changes from core 5e rules. Larian do their own version of 5e rules. Elemental surfaces are fun, make the map layout and positioning absolutely crucial, and allow for much more tactical play. Some people get hung up on minute differences from 5e: maybe enjoy the game as it is, if it doesn't work in the game, then critique it in those terms. 5e isn't a bible and it's not useful to be fundamentalist.
I played D:OS 1 and D:OS 2. I enjoyed D:OS 1 and D:OS 2. This is a completely idiotic "hot take".
- For starters, Larian themselves have advertised this game as being based on the D&D 5e ruleset. They did not say "Based on the Divinity: Original Sin rules."
- Don't tell people to stop complaining about the differences between 5e and this game. Larian does Early Access for a reason, which is specifically to get feedback. If you like the system as it is now, great, fine, that's feedback, and you are free to give it. Don't tell others to shut up.
- I will now explain the reason for the complaints. It is not a reflexive, knee-jerk aversion to change.
- Divinity: Original Sin 2 is balanced on the idea of being fully charged with all abilities available for each and every combat. Tactics are King.
- Dungeons and Dragons 5th Edition is balanced on being fully charged after a long rest, and then having resources and options slowly whittled down over the course of a day. Resource Management is King.
- BG 3 is using Hit points, Armor Class, and Spell Slots for players from D&D 5e. They are using the Concentration mechanic from D&D 5e.
- Monster HP in BG 3 is usually higher, Monster AC is usually lower, and Ability scores remain the same.
- D&D's HP, AC and Concentration is not balanced around the idea of status-inflicting surfaces, status-inflicting attacks, and AoE attacks to be as prevalent as they are in BG 3.
- Just about every single surface effect in D&D has some kind of saving throw to resist for half or no damage. There is no such thing as a guaranteed hit from a surface.
- Concentration spells are balanced around a roll under 10 or half the damage losing concentration. The more checks you have to make, the greater the chance you will fail. You are far more likely to fail checks because you're doing a lot more of them.
- Enemy HP is way up, enemy AC is way down. This makes spells balanced around on hitting AC more reliable. This makes spells which affect a certain amount of enemy HP far worse, such as Sleep and Color Spray, because they can affect fewer enemies.
- Enemy saving throws remain the same. This makes spells balanced around enemies failing a saving throw will seem to suck more because they're doing less damage. Example: Sacred Flame - it does 1d8 - an average of 4.5. Fire Bolt does an average damage of 13.5 from what's supposed to be a 1d10 spell.
- Armor Class is based around advantage being relatively rare. Statistically speaking, Advantage is an effective +4 (Disadvantage an effective -4). Constant advantage from high ground is and disadvantage from low ground means those on the high ground are dealing more damage, those on the low ground are missing more and dragging battles out longer than would be normal.
- Larian has changed many things from 5e, but have left other things as standard. That does not work. The systems have different design goals in mind.
What a sober review of how bad those features from DOS2 impact the game balance. Couldn't do it better.
One thing is to add some flavouring in the game as they've done with the weapon skills that recharge every long rest (it even could be every short rest and it would be also ok). Other thing is completely break the essence of DnD which is based in progression (resource and action economy/management). I don't want to fight battles wiith full spell slots and full health. I want to regret decisions I've made with me resources by casting that Guiding Bolt in a minion and now have to deal with a bigger threat without it.
I'll list some refurbished Larians features that they added to the game because they think they are key success factors for every game:
High ground advantage
Itemmancy - Thousands of items - Quality over quantity
Surfaces
The necessity of having plenty of actions to do in one turn
The necessity of having battles that feels epics all the time
The comprehension that battle skills are a must - just rolling a sword attack is boring
Magical Arrows - because archers are boring
Infinite rest - because a game without bedrolls are nothing but a bad game
Particles - because a game without particles sounds too 20's
Lack of freedom - because you are going to make clever decisions that I've added in the game whether you want it or not.
No sense of attachment - I encourage you to respec your character whenever you want. No regrets.
No punishing - Everything can and will be fixable
Well, I can spend the rest of my day listing how they've built the game over DOS2 but there'll always be someone too fanboy to see.
I guess the main problem is that everyone is trying not to hurt Larians feelings while losing the capacity to think rationally.