To me, things are always simple.
When you work towards what God has created, you have HIM on your side.
Did He created C-Section? It was men!
Go for natural. That's what our (woman) body is made for. The complications of C-section can be unimaginable. My sister In law, my friends, did it and only 1 DID NOT regret doing it. Because that '1' had health problems, she was FORCED to go for C-section right from the very beginning when she found out that she was pregnant.
If you do not have health problems. Why choose to go under the knife?
YOU Mentioned about the Natural birth disadvantages:
1) Possible damage to pelvic floor
- which may affect my future sex life with my husband(or so I am told by some male colleagues)
Seriously, that is not true. So long as after your virginal has healed, you should start doing the 'contraction exercise'. What the man wants is tightness. Has nothing to do with the pelvic floor. Get that part of the 'muscle' moving again. You two can enjoy 'bedtime' as much as before.
2) Uncertainty - I may have to opt for c-section last min if natural delivery doesnt work out
Never think of what is to come. Because all these are in future tense. Do you know what will the weather be like tomorrow? Even the weather report could be wrong. So THIS is no reason or even excuse at all to opt for a C-section.
In my opinion, nothing beats anything that is NATURAL.....in anything...