Honestly, I would wait and see. Give them time to adjust. I don't think I would add more or larger birds until you know for sure.
I purchased hens that were shipped from Indiana to Ohio, it took two days for them to get here. One hen starting laying right away the second one waited for 2 months. She and I sat down and had a long talk. I explained to her, she needed to start earning her keep or into the stew pot she was going.
Well, I guess, I wasn't specific enough, because she starting lay eggs in the woods and it took us almost two weeks to find them. Ohhhhh well, she's a laying machine now.
The only thing about banty eggs are they are small. So you may want to crack a large egg into a measure cup and see how much is there. Then crack the banty eggs into the measure cup til you get the same volume.
JMO
Tracy