Unsure if it will be ineffective due to excessive skin laxity - Is Renuvion/ Jplasma sufficient? (photos)

Renuvion/J-Plasma is a minimally invasive skin tightening treatment that uses radiofrequency energy to tighten and lift loose or sagging skin. While it can be effective for mild to moderate skin laxity, it may not be sufficient for more severe cases where there is a significant amount of excess skin.
If you have excessive skin laxity, a surgical procedure like a armlift may be a better option. A armlift can remove excess skin and tighten underlying muscles, providing more dramatic and long-lasting results.
It's important to consult with a qualified plastic surgeon who can evaluate your individual concerns and determine the best treatment plan for you. They can help you determine if Renuvion/J-Plasma or another treatment option is the most appropriate choice based on your unique needs and goals.

I have seen very good results with liposuction and Renuvion in women similar to you. I would suggest going with Renuvion. Later, if not tight enough, you can always do the excision. However, the long scar does show.

From your photos you will have the best outcome from a brachioplasty. Liposuction will remove some of the fatty tissue but you may still have lax hanging skin even with J Plasma. I've included a video on brachioplasty that I hope you find helpful.