My IGM was the high one too. My Kappa FLC are now 379 which puts the ratio K:L at 44.6 when the "normal" maximum is said to be 1.65. I believe I may have peripheral neuropathy in left-hand fingers but my doctors say it is a flow challenge arising from my extensive use of bike handlebars when biking.
I believe the recommendation to just "live your life" is a good one. Look after your diet, your exercise and your medical care and always remember your doctors see many people per day. You get to see you every day. You do need both to be looking out for you, but your own self-care is likely to be the most important.