Thanks for your response. It was exactly what I needed to know. I'll made an appointment for that second opinion on the treatment to follow. I'm now inclined toward the ablation.
Remarks from the doctor/patient forum seem to be with the silent afib, "If it ain't broke, don't fix it." However, at some point the heart does seem to develop problems. For instance, my sibling next up to me (I'm the youngest of 6) is having open heart surgery, valves and blockage, this week. As with all my siblings, he has afib. Because of this forum, and especially your encouraging reply, I suggested he talk to the surgeon about having ablation also at the same time.
Second opinions are always worthwhile if you have the kinds of questions you posed. Certainly Cleveland Clinic should be able to help you choose the best option.
Weighing the risks of treatment is difficult. I chose ablation, which occured two months ago. It appears to be successful. My aunt, who is 70, had ablation a year ago, and it was also successful. As you are aware, there are risks. A second opinion from experienced people will help you sort that out.
Best of luck to you.