During this period, I will say weekday is better cause now is not school holiday, so technically there should have lesser people. Not sure about the current arrangement on feeding. You can go to the website to see the announcement to confirm which attraction is close for maintenance. Maintenance is usually done on weekdays cause lesser people.
Regarding the coverage, depending on how long you will take to complete the whole route. But my suggestion is to go either one and not both on the same day.
Free birthday entrance can go to the website to check if it has open up.