Hi Athena,
Read the thread, and DW/family has experience in this, thought I would share our experience for your reference. Will be long...
She was diagnosed with MVP in her early 30s. Put on beta blocker by GP. She could feel what she called "skipping a beat". Was never much for exercise (personality, heart function, who knows). I could always do more, a 5 mile hike at 10K feet was doable, if slow, well into her 40s.
Don't recall exactly, but sometime in her 50s her GP said you should see a cardiologist regularly. At first the cardio doc said, you might need surgery at some point. That progressed to, you will need surgery at some point. Then one visit he said, you need surgery now, but it was at least 10 years after starting to see the cardio doc regularly. I don't recall ever hearing about EF numbers, despite them being mentioned regularly on med sites.
Her brother and two nephews were diagnosed with the same problem and had surgery (two before her, one after), her brother was replacement (went great, but unfortunately he passed from cancer about 16-18 years later, his cardio doc said the valve was great and something else will get you, he was right). Her two nephews were repair. The youngest nephew had his first repair at 39, opted for the minimally invasive. This was over ten years ago. That repair was not great, and he has since needed a second surgery, he opted for the sternum crack, and said "difference in recovery was not that different, and the repair wasn't as good with the minimally invasive". Based on this, the second nephew opted for sternum crack. That's been several years and he is doing well.
When we were getting to the point of "surgery is going to happen at some point", her cardio doc suggested that we consider traveling for surgery if we could handle it financially. Medium sized town in midwest, her specifics of leaking were at the difficult end of repair vs. replacement, and suggested specific surgeons at Cleveland Clinic and Mount Sinai NY as options (most surgeons would not even attempt a repair, per the regular cardio doc). When we got to the point of "you need surgery now", there was a new local surgeon, and he was now on the recommended list. This was 7 years ago and her surgeon said minimally invasive is not an option. There are lots of details as to when it may or may not be considered, and everyone's situation is different.
Surgery done, recovery normal, which is to say it takes a long time, maybe a year or so. Not just the crack the sternum, but the whole shebang.
She didn't come back to doing the types of activity you mentioned, but after 10 years of not doing a 10K foot mile long hike, she did it again. Improved? Yes. Like she's 40 again? No.
Fast forward to today. She has other health issues that are more of a problem, but sees the cardio doc regularly. We now live in a different, smaller, town, with new docs. During her recent echo the tech (in his 50s, I'd guess, experienced), said it was one of the best repairs he'd ever seen. Having a good surgeon makes all the difference!
One thing I found interesting... the surgeon she used was a medium aged guy, old enough to have experience but young enough to be up on new techniques. I'd never given it much thought, but her regular doc said very few older/experienced docs at the time she needed the surgery would have tried a repair, when they were learning her situation was only repair.
AF was mentioned, she went from occasional to persistent AF. Drugs, ablation, they kept her out for awhile but now it's here to stay. The "does MVP cause AF, or vice versa" question is out there. Either way, it's a progressive situation.
I wish you the best!
Your situation doesn't sound as bad as hers or as extended over time, but things can change in a heart beat... OK, bad pun...