That sounds like a fantastic update for the All-in-One Easy-to-Install Texture Pack V6.0! The addition of new grass textures can really enhance the visual experience of the game and make it more immersive. It's also great to see that you have removed the Tire-Physics feature and suggested using the Realistic-Weather-Mod instead. It's important to ensure that everyone in multiplayer has the same textures installed to avoid any issues, so it's nice to see you mentioning that.
It's also wonderful to hear that you have asked the creators of the textures for permission before using them. Respecting the work of others and getting their approval is crucial when adding custom content to a game. This not only shows courtesy to the creators but also ensures that the content is used in a fair and legal manner.
Overall, it sounds like the All-in-One Easy-to-Install Texture Pack V6.0 is moving in the right direction with these updates. Players are sure to appreciate the visual improvements and the attention to detail in making sure the textures are used correctly. Keep up the great work!