RE5 is better than RE4 (2005), so I'm going to elaborate further:
- Better support character. I love Sheva and find her much more interesting than Ashley. Yes the AI can be a mixed bag at times, but as long as you arm her with a sniper rifle or machine gun, she works fine. It's the same vice versa, if you're playing a Sheva and let the AI control Chris. I do wish we got to see more of her actual backstory and not just found it file notes. Seriously Capcom, you couldn't give her a brief 2 to 3 minute flashback?
- Though more linear than the previous game, it's not a bad thing. The levels don't drag on, and they're still plenty of open ended levels where you can take side paths that rewards you for finding hidden collectibles, or taking the risk with enemies involved.
- Easier quick time events*. Granted, this is only available, if you have the 8th generation versions of the game. The qtes are still not that bad, but they are more difficult when playing on the harder difficulties.
- You get better melee options. Chris, Sheva, and all the characters featured in Mercenaries have better melee options compared to Leon or those in RE4 Mercenaries. You get literally three or four melee options based off where enemy is hit, if you're in front or behind them, or if they're on the ground. If you kneecap a person and then go behind them either character has to move that counts as an instant kill when the button prop comes up. I can't wait to see you what they pull off for RE5R. I will bring up my possible guesses and theories in the Resident Evil thread.
- And even better Mercenaries Mode, that is unlocked from the start if you have the PS4 or Xbox One versions. The other two bonus modes are fine from what I remember, but I haven't touched them. Most fans like Lost in the Nightmares, but dislike or mixed about Desperate Escape. All I know is that they're both still better compared to Separate Ways and Assignment Ada.
- A much better story and original closing off point for the series. Yes, I said it. I know people like RE4's story for how "so bad it is, good" but I never cared much for it, until RE4R made it great. Mikami has long admitted he hates the story, and the fact that he rushed it with all the script he writes and only had two weeks to do it.
- Much better pacing. The fourth game is technically shorter, but drags pretty much as soon as you get to the island. 5 goes have some drag, but it's nowhere near as long and it goes by out of brisker pace as far as I'm concerned and experienced.