Congrats on 675!
Most improved and perhaps the only improvement you can consistently gain would be in DI.
I would encourage you to approach that section without doing calculations in most questions in graphs, tables, or MSR. These questions should not require you calculating exact numbers but instead you should focus on looking at trends (increase/decrease) and fast estimations.
P.S. Unless you find it easy, I would say anything above 705 would be sufficient. To reach this score, you will need to get 7 sectional points among V, Q, and DI. Figure out how to get the sectional scores up by 7 points and that will be sufficient.