Skin retraction after liposuction with or without skin tightening depends on initial skin quality. I think your concerns about creating more loose skin are valid. In general, “skin tightening” procedures can be effective but are less predictable than excision procedures. Based on you pictures it seems reasonable to start with lipo + bodytite/renuvion. It does not preclude an arm lift in the future. However, in person evaluation would be very important to assess the overall skin quality.
In my opinion, you are unlikely to be satisfied with anything short of a tummy tuck. Based on what you’ve shared, I believe skin tightening devices such as BodyTite, Renuvion, or Morpheus would not deliver results that justify the investment for your abdomen. That said, your thighs may benefit from BodyTite or Renuvion, though an in-person evaluation would be necessary to assess your skin quality and determine the best approach. Your concern about keloiding is reasonable, but I would recommend speaking to a plastic surgeon about your keloid history to get a better idea of your individual risk.
