Should I have capsules removed.
Usually in the absence of contracture or a silicone leak, the capsule can be left in place. The problem with leaving the capsule is seroma as you mention, and they do resolve over time. The risk of capsule removal is bleeding, loss of breast tissue, and seroma formation. Yoursurgeon will have a good look at the capsule when your implnats are removed, and his experience will guide him.
That's a discussion to have with your plastic surgeon. If the capsules or portion can be removed safely, that can be determined during surgery. Clearly thickened or abnormal areas should be removed if there is little risk of skin or soft tissue damage. Otherwise, leaving capsule should not cause significant problems .
Implants not related to connective tissue diseases
I am sorry to hear about your condition. While it is natural to want the implants removed "just in case," there is no credible evidence to suggest that removing them with or without the capsules will have any effect. The condition you are unfortunately experiencing happens in the same percentage of women without implants as those with them. If you do proceed, the capsules should be at least partly removed for a lower chance of seroma.