I am afraid that all the things related to Pensions are complicated.
Personally when buying annuities I have always opted for "level income" without "spouse pension", but with either 5 or 10 year guarantee. I constructed an EXCEL spreadsheet to help with my decision.
When you reach pensionable age I suspect you will be given various options. They will probably include questions like, "do you want your pension to increase each year, and by how much" giving an option of RPI,5%,3% etc., "do you want a spouse pension and how much of your pension should that be" etc. The Pension provider will then give you details of annual pension income, dependant on the examples you request. The booklets you will receive are very informative. But to be honest I found that increasing "pension income" and "spouse pensions" options resulted in substantially lower initial personal pension income, which took ages to catch up to a "level income" option. AND if your spouse does not need the income why take a lower income now to provide a small income in the future for someone who does not need it!