You need to decide what's best for you on your circumstances. There's so many variables that it's unhelpful to compare with other people with possibly wildly different priorities and needs.
People also define savings and structure their money in different ways such that a number is effectively meaningless. It's also unclear as to whether you're single or have a partner as you talk about I a lot but then mention maternity leave indicating a current or former partner, so another income or possible child maintenance. All this would make a difference, as would job security, current disposable income, lifestyle preferences, marginal tax rate etc etc.
In your position, building pension savings is important but not at the cost of short/medium term security, especially if your income is insecure and you'd struggle to cover the basics if you lost it. It's also relevant that you'll be able to address your pension later on, once childcare costs have dropped, income may have increased due to career progression and mortgage will have reduced, although it's worth bearing in mind that mortgages are very cheap debt, so you'll almost certainly come out ahead if you let it run it's course and invest spare money instead.
The financial flow chart is a good 'to do' list to work through, so you can see what you've already got on top of and what needs more work, but it's probably not a question of prioritising one or the other but saving some, putting some in a pension, paying all your current bills and expenses and deciding on what level of lifestyle fits in with all this and your current income.
Have a look at:
The UK Personal Finance Flowchart | UKPersonalFinance Wiki