Basil sugar pound cake lemon sensitivity

I think any citrus will work well here. Even grapefruit!

Yes, I think it would. I have found it ok to switch citrus in both sweet and savory dishes.
If you're not sure you will like the new version, make a small batch to test.
If all good, full speed ahead.
If not, look for another flavoring to replace the lemon or another pound cake recipe.