You did well out of good luck due to the timing of your investments
Stock market averages greater returns than mortgage rates over the long-term so that’s no issue, annuity mortgages were not so good due to the high costs as much as anything.
going for straight repayment is nothing to do with being financially unaware
Well if you’re not financially aware it’s best not to start picking investments you know nothing about – and may start worrying about. Some financially aware people may choose repayment mortgages of course. I ended up paying my mortgage off just because I could, if I’d been more comfortable with risk I wouldn’t have but it created a good balance with the amount I had invested.
Well you could do worse than look at hargreaves lansdown’s Wealth 150, I also use Close Brother’s scoring info on funds. I used to work out annualized returns but got bored with that – averaged around 8-9% returns over last 15 years though, my mortgage must have been around 4-5% over that time – I have a base rate tracker offset mortgage of 0.49% over base rate (which I don’t owe much on now).