1. It is recommended to pull-up I2C SDL and SCL line with 2K resistor. This can varied based on your line capacitance
2. Put the test points for PCLK_test, HSYNC_test and VSYNC_test pins - H8, G6 and H5 respectively. This will help you in debugging.
3. You may also put a header for UART pins - this will help you in debugging
4. You need to modify the power connections (Bulk Cap and Decoupling Cap) in CX3 Schematic
5. Looks like you are using one of the pins XRST0CX3, XSHUTDOWN0CX3 using a Jumper (JRST).
These pins can be used as follows:
XRST : Image sensors usually require a reset signal from CX3 before configuration. This reset can be done using the XRST pin in CX3.
XSHUTDOWN: When the Host is not requesting a video stream from the image sensor, the sensor can be shut down or put in a standby mode to reduce power consumption. This is done using the shutdown pin in a sensor, which can be controlled using the CX3 XSHUTDOWN pin.
You may connect both the pins to Sensor (if the sensor has two pins for reset and Low Power mode). I couldn't see XRST_CAM connected to the Sensor (OMV6211).