The east and west facing sound like a good idea to help boost early morning and late evening solar generation, but I would suggest only tilting to 50 degrees so that it operates more effectively throughout the morning and afternoon (otherwise, it might not be able to charge the batteries during the day). Can you start the pumps at sunrise rather than 5 am when it’s still dark?
East and West strings in parallel into one MPPT will work ok. It is quite common to use this configuration, but it only works when the strings are the same length (same number of panels).
Have you considered a Deye SUN-12K hybrid inverter? They have dual MPPTs, so you could have two separate strings. Also, the Deye inverters are better quality than Growatt.