1. If you can get very good GMAT score, together with your grad GPA, it should offset your low undergrad GPA. However, I think some schools do have certain requirement on the minimum GPA. Please check with the respective schools.
2. Most of the schools that I am looking at state that working experience is not a requirement. But I think having good and relevant work experience will help to differentiate.
3. If you can have strong LORs and SOP, I think it should offset your lack of work experience. Ultimately, the ad comm is more interested in your research abilities, which you can emphasize in your SOP and get your recommenders to do the same in the LORs.
No recommendations for schools, as my focus is in another discipline.