You will spend a lot of time in the chair you will be nursing your baby in, and whether it is breastfeeding or bottle feeding the needs are the same. It must have a nice high comfortable back. It needs sides that are not hard or too high as your elbows will want to rest there. If you can find one with a matching footstool or get hold of a moroccan pouffe your feet will thank you and, as baby gets bigger, you will find having your legs elevated will help balance your baby once they are no longer completely supported in your arms.
You also need to be able to get out of the chair without drama when holding a fallen asleep baby. Wake the baby or call for help? No. Way.