iwouldnt put them both on the left but more like a shift an inch over
i wouldnt add wieght to the front either because once you get it set up correctly then it will be robbing you of speed.
you dont need trim tabs if you set your boat up correctly.
btw can we see a pic with all of the electronics and batts in it please, thanks then maybe we can help you more.
mike

how high up in your hull do the batteries sit? if they could be moved lower you could try that