I recommend going to the Blue Mosque near the end of the sunrise prayer (about 60-90 minutes after the prayer start time), unless it's a Friday when the schedule differs. You might have to wait a few minutes for people to leave, but there was basically no line to get in and the crowds were manageable compared to later in the day. The RS guide book covers it well.
The Chora Church has been converted to a mosque, so someone who has been recently can weigh in on whether the RS content is still accurate. There is an update on the guidebook webpage about admission cost, opening hours, etc. https://www.ricksteves.com/europe/turkey/guidebook-updates.
I know you like tile work, so I also recommend going to Rüstem Pasha mosque, near the spice market. Our RS tour guide recommended visiting and I'm glad I took her suggestion. It is relatively uncrowded and has really beautiful tiles, because it is a small venue it's a little easier to take in than the Blue Mosque.