Its about getting comfortable. It's what works for you! My favourite position changed over time as my little one got older and bigger. Find those that suit you best. This could be because you have bigger breasts, or purely for latch and comfort.
It can take some time to get the hang of some of these positions in the beginning. It does take some time, but you can adjust to suit you. Use pillows to support your back, make yourself as comfortable as possible.