OP is actually looking at the wrong game. This is an RPG with a specified character, you can roleplay his decisions but he stays a swordsman with access to basic magic.

I think what the OP may be referring to is the streamlined meditation / potion / oils / skills / crafting system. The original witcher had an excellent system. Building on this subtly would've been much more effective for an immersive RPG. Everything is quite basic right now. In the first game you actually had to meditate to prepare potions etc.. It felt much more like you were a witcher. Alot of this is now done for you in this game it takes away from the best elements of the series

Have you played Witcher 1?

The streamlined meditation lets you focus on exploration and the story itself. I would hate to farm for ingredients like an idiot. I play WoW for that :P Besides, isn't that a very subjective opinion? Some will like it and some will not. Problem here is that Geralt is the master Witcher. He is around 100 years old here. What exactly do you want him to build upon?

In Witcher 1 he had amnesia. In Witcher 2 he had less amnesia. In Witcher 3 he is fully developed. You could make the oils, potions etc. more complex and demanding but...in the end it is just a matter of opinion and personal taste. For an immersive RPG you have hunting contracts, side quest cutscenes, side quests with a heart and soul etc. What is more, you have a totally different setting. This is not a western RPG. Weapons and armor crafting is complex enough. I dunno, this doesn't bother me much. I am happy with what I got. It actually annoyed me in Witcher 2 that I could stack oils and potions in tremendous amounts of hundreds. Whats so immersive about that?

I played every game in the series. Meditating just for crafting potion DOES NOT ADD any roleplaying element. IT SUCKS. Grinding for ingredient SUCKS. GRINDING SUCKS! I prefer going through the story elements instead of grinding.

When TW2 required you to meditate first before you can drink potions, people complain, now that you can use potions while in combat, people complain. No pleasing these people. sheesh