5e RAW is extremley barebones and only the biggest of contrarians call it a good system.
I call it good at what it wants to be. But yes it is a barebones simple system but that is intentional.
I come from Germany and we got a locally successful RPG that was super complicated (TDE 4.1 edition). Like it had an insanely detailed magic system with countless subsystems that worked completely different like for summoning demons, creating artifacts, each school of magic (elves, witches, druids etc) had own special rules and for combat it tried to model weapon reach advantages from dagger range to pikes or endurance in combat and weapons breaking.
That said I once GMed a combat against a town guard that lasted 14 hours with that system you won't have that problem with D&D.
D&D is neither good for simulating "realistic" medieval combat nor do any of its settings have very well made and described medieval fantasy societies. It is a great system though because of its iconic mechanics & art, richness of its publication history and countless creative options it brings to the table while still being easily approachable for new players.
Yes, I have played Realms of Arcadia trilogy, based on DSA (not sure about the version, the games were from 1991, 1993 and 1995).
They used exactly the PnP rules which meant:
- 80% of spells and skills were useless because they could not be implemented in a computer game at that time, some of them would still be hard to implement today.
- Combat took forever because most attacks miss, get parried or they are absorbed by damage reduction.
- First you had to use one spell to see if an item is magic at all and there was another spell that told you the exact magic effect. Both spells could fail because of low skill or bad dice.
- At level up you had to roll dice to improve a stat or skill. This could fail so in the worst case a new level gave you nothing but a few HP. These points had to be split between HP and MP if the char could cast magic.
- The level up screen came directly after combat was over. No way to save and then press the lv up button. If you dislike the lv up results you have to do the fight again.
- In the first part every party member lost one exp every time you saved the game outside of a temple. You gain exp at a very low rate.
summary:
- It is good that DnD 5E rules are rather simple
- It makes sense to change some things if you adapt a PnP game for computer.
- This does not change the fact that I dislike the D:OS item system. Loot should be relatively rare in general and magic loot should be very rare and hand placed.
Prof. Dr. Dr. Mad S. Tist 
