Yes, I can assure you as a member of the team who is working on this project that Lizardmen (along with the new factions of Wood Elves and Ogre Kingdom) will offer a unique gameplay, mixed between their units roster, mechanic and their own specific soundtrack ( ogres instead use the same of Orcs ), the same also for Tomb Kings ( dark egyptian like music) and Chaos Dwarves/Skaven ( the last 2 have new music instead of those arabic present in the original COW), in general almost the 80% of the tracks that will be present in the submod are totally new ones.
About the scripts we have chose to remove most of them because
1) usually they were responsible of a major instability and cause of ctd on original COW at cause of wrong entries or letters or numbers in the files
2) and as you said limits the replayability, because once you played many times you already know what will happen and how to deal with it
We prefer to have little script and to leave players to choose how to play the campaign with their decisions instead to follow a scripted and specific plot. Only the start of the campaign will show the lore situation of the warhammer world at the start date, but then everyone is free to do what he/she wants on how play the campaign, which i assure will be different everytime you choose a different faction ( maybe at max only imperial factions could be similar in gameplay )
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