I just took the TEAS, so I can definitely help answer your questions.
1) There are no pictures/diagrams in the science portion of the exam. So, no need to stress about that.
2) The ATI TEAS Study Manual is NOT detailed enough. I cannot speak for the "crash course" you mentioned, however. I would recommend buying the ATI Practice Exams from ATI's website. Those are the best gauge as to how well you will do on the exam overall and will let you know what areas you are weakest.
For A&P, Biology and Chemistry refreshers, I watched a YouTube channel called "Crash Course". Hank Green does a phenomenal job of covering these topics. Each video is roughly 9 to 12 minutes in length and there are 40+ videos for each A&P, Bio and Chem.
To give you an idea of how much those videos helped, before watching ALL 46 A&P videos, I scored a 72% on the science portion of the practice exam. After watching the videos, I scored 89% on the second practice exam. My overall score on the first practice exam was 84.7% and my overall score on the second practice exam was 92.7%.
I ended up with an overall score of 92% on the actual TEAS, with an 87% in Science, 100% in Math, 96% in Reading and 79% in English.
Honestly, with your background in A&P, Bio, Micro, Chem and O-Chem, I think you should be good. Unless you miserably failed those classes... haha