1. 70 points on 2613 should get you an invite the very next round after EOI submission. Provided you get the ACS assessment as expected.
2. Not aware of such a secretive list. And certainly, migration agents are not a bunch of special people with whom the DIBP will share such information with, even if it exists. My interpretation of the information on DIBP website is that you must have your qualification assessed in order to claim points. However, check this information with DIBP before taking a decision.
3. Both you and your spouse can submit individual EOIs. Current cut-off for 2611 is 70 points with DOE of 7th June. An EOI with 75 points should get you an invite in the next round. However, please ensure you don't end up with invites on both the EOIs. You will only apply for one VISA, while the other will be wasted which otherwise could have gone to another deserving applicant.