Breast Expanders, how much to fill first time?

Its really hard to give you specific advise without pictures or an exam. In general, a big change in breast reconstruction is getting enough profile in the implant to avoid the "flat" look you are describing. In my practice I tend to use ultra high round implants or shaped high profile implants....

After mastectomy there is less skin. To remove more in any pattern is not wise unless it is replaced with a lat doors flap. This is a good option and adds better tissue to cover an implant.The nipple and scar will likely be improved. In experienced hands this can give an excellent long term result.

If it is MOndor's cords, then this is superficial thrombophlebitis which often improves with warm soaks and anti-inflammatories. Best to be seen by your surgeon.