When pregnant there were a couple changes I made:
Ate the same breakfast every day so I could catch when my insulin dose needed to increase
In the 2nd trimester I couldn't eat high carb or high fat food after 5pm. It took too long to digest and I'd have delayed highs.
My goal was to have a non-diabetic A1c with no severe lows. I aimed for a target blood sugar of 80 and tested often to make sure I didn't have lows.
What's the point of using a pump if you're doing to eat 60g meals and 15g snacks like a robot? I didn't limit what I ate and didn't have a strict diet but got diligent about carb counting. I also would bolus, eat and then test an hour later to see if a correction bolus was needed. That kept my postprandial numbers lower.