In the nicest possible way, you have only ever seen low risk births. When you have a bit more experience you will be a lot more aware of what can go wrong, and the what could have beens.
The staff at my unit say labour is normal until it's not
Well yes. And sometimes it stops being normal in a second. I have friends who had lovely low risk pregnancies and textbook births, then baby born blue with apar of 1 and mother had massive haemorrhage. No one could have predicted it, that's why we have midwives, in case it all goes wrong. To follow your logic, why bother having midwives at all, give partners a pair of gloves and a clamp and an emergency buzzer for when it looks like someone's dying?!
If I was giving birth I would prefer to have a qualified midwife than an MCA, no matter how nice she was.
Why do you think your unit is paying MCA's instead of qualified midwives? It isn't because they think they will do a better job, it is to save money. None of your colleagues are going to tell you to your face that they would much rather have a qualified colleague than you. I don't point out to my less experienced colleagues that I can do their work in half the time why would I? It would be rude and unhelpful. Doesn't mean it's not true.
the parents didn't complain afterwards that someone with far less training than a midwife was involved
Because they didn't know that you had so little training, and they didn't want to think about the fact their baby could have died. If that baby had died or suffered permanent brain damage and a midwife could have saved it, how would you have felt?
That someone hasn't died or been injured due to the working practises in your unit yet, just means it hasn't happened..... Yet. It doesn't mean it's the best way of doing things.
I'd like to think that my body is capable and my efforts are enough to deliver my own baby, with a midwife and an MCA at the end if necessary
Apart from anything, please rethink this attitude before you look after labouring women by yourself. Sometimes everything goes tits up and it isn't because a women's body is not capable or she isn't trying hard enough.