My workplace offers 6 months full pay, 3 months statutory, then 3 unpaid, and your continue to accrue annual leave while on mat leave (so long as you take it immediately prior to returning). So in practice I didn't take all the unpaid time, and swapped some of it for a/l. I was also able to choose to top up my missed pension contributions from while I was off, and they then paid their element of that.
The fact that my workplace has a really good maternity leave entitlement is one of the things that kept me working there in the long term, even when I had some rougher patches with my job. Maternity leave (as with sick leave, other types of parental leave, etc) is not some favour they're doing you - there's both the legal requirement to offer certain things, and then there's the business case for doing so. In my mind, a workplace that doesn't offer anything over the minimum is... meh. Not somewhere I'd be looking to stay.
In your position i would shoot for the stars. I would look around for really good examples of maternity, paternity and adoption leave, shared parental leave, etc, and hold them up as the ideal to which the company should be aiming. Because they should! If you can find examples from within your industry or local area, that's a bonus. Yes, these things have a financial cost to the company. But they also have real benefits in terms of staff retention, loyalty, and happiness.
You may not get what you propose, of course. But if you go in rather diffidently saying, 'well, legally, you have to give me x' then it's sending one message. 'Here's a vision of how we could write some amazing family-friendly policies for our workplace, and examples of best practice' sends another, and I'd go with that. And including all types of family leave in what you talk to them about navigates any weirdness about being the only woman there.
Congratulations and best of luck!