Unfortunately I don't think I have seen any other books like the Ripple System, so I have none to suggest. However I will upvote and add to the thread for visibility and hope to see some of these suggestions myself.

There are very few books like Shadeslinger (The Ripple System book series). It handles the VR-MMO trope seamlessly. While still managing to give the events stakes, which is something many authors struggle with when using that particularly concept for their series. Usually all stakes in the 'game world' are lost in such a setting and stakes are created in the form of a sick loved one, a climbing debt, being stuck in the game or some other convoluted issue.

Even Black Sand Baron (The Ripple System Book 2), which is quite good, falls into some of the traps prone to such series, it follows in-game events virtually to the exclusion of the outside world for example.

However Black Sand Baron also does something very, very few LITRPG books manage to do, it includes the RP part of LITRPG; role-play, where the protagonist is acting as an individual different from their own innate character and it is accomplished this through an interesting use of the mechanisms set up in the gamified world. So you have the protagonist (Ned) who has one persona and his merchant alter-ego which has another persona, so he's clearly playing a role when he dawns that particular character.

I only mention it primarily because the 'RP' element of litrpg is often entirely forgotten and it's one of the areas the VRMMO setting could potentially corner and one I essentially never encounter it in my reading. Mild mannered computer programmer by day, evil megalomaniac conqueror by night all in one person.