I don't think you need to book entries to any of the sights you listed. (In fact, I'm surprised that the Frida Kahlo Museum recommends advance tickets.)
As you wander around Oaxaca, you'll find a lot of tour companies that offer day trips to Monte Alban and other nearby attractions. The problem is you have no way to gauge how good their tours will be. I booked a tour to Monte Alban that they said would be in English, but it turned out I was the only English-speaking person on the tour, and it was offered entirely in Spanish. (My Spanish is not good enough that I was able to learn anything about what we were seeing.)
So you might want to go on Viator or GetYourGuide or ToursWithLocals and see who is offering some of the day trips you're interested in. Then you can at least look at reviews and find the tours that go to the specific places you're most interested in.
For many of the sights in Mexico City, when you buy tickets, you'll encounter tour guides waiting at the entrance offering to give you a guided tour. I've not ever hired any of these guides, but I've heard that the experience can be good. And I've overheard some of these guides and eavesdropped, and they seemed to be knowledgeable and interesting.