The most effective incentive for users is likely the ability to save time and effort.
For example, it would be a great case study if users could participate in governance using ASTR tokens on Soneium. The fact that users can do this directly on Soneium without needing to transfer tokens to Astar L1 is particularly convenient.
Agree with this realistic usecase! If this can be done without any serious technical challenges, then other crosschain usecases can also be proposed and tested for sure.