I've been in and around the community for almost 3 years now, since the inception of the pack.
It is a very well-detailed and balanced expert mod pack that includes many different mods. The pack follows an atypical structure of non-linear progression, interweaving mods at various stages of progression, as opposed to your average linear expert pack (which revolves around doing one mod at a time). Documentation is included in the questbook itself, covering most of the major tech and magic mods, as well as comparing the differences between features from different mods that may have similar functionality.
This modpack relies heavily on automation and exploration, which are interconnected as exploration contains puzzles that yield QOL rewards that improve the grind of said automation. The pack demands that you automate everything, and provides multiblock alternatives (after finishing puzzles/challenges) for those that may be slow or laggy. Additionally, ProjectE is introduced to the player at the very start of the pack, in Chapter 2 (around 50 hours of gameplay), as there is a focus on complex crafting chains and unique mechanics rather than mass resource collection.
Stability is exceptional in this modpack given many included experimental performance mods and custom mods written by the community. Client performance can be improved significantly by following the Java22 instructions on the wiki page as well. One thing to note, however, is that, as Meatballcraft is an ultra-large modpack, TPS management is necessary to maintain playable server performance, especially in mid-late game.