A This is a good question. First, you are taking the correct first step to have the lump biopsied and fluid around the implant checked. With all the recent discussion of textured implants, seroma, and concern for ALCL, this is a mandatory workup.
Implants can have inherent issues whether saline or silicone, but generally saline implants over the muscle can cause more rippling. Factors such as breast tissue thickness, implant size can influence degree of rippling. Also, a structured saline implant is an option. This implant has internal scaffolds which can help limit implant collapse. You should have a detailed conversation with your plastic surgeon.
Best