Based on UK average x 2 12 hour days childcare alone you're contributing £100 a week to the household that's approx £430 a month!
Then include all the housework you do that's more than your share? Quick Google says £12 an hour.
Then the weekends where he's apparently doing bugger all to contribute to family life! Does he even do the grocery shop with you? Laundry? Clean the loo ever? Mop floors? Windows? Dust? I bet not! So you're doing the majority of the housework.
Now that's just the practicalities.
Then there's the fact he DOESN'T WANT YOU TO KNOW what he earns RED FLAG
Argument every time subject raised RED FLAG
Does he have life and critical illness assurance? With children he should. A will you should both have.
This is as pps have said NOT an equal and respectful relationship. It is an arrangement whereby he ALLOWS you to have children as opposed to this being a joint decision and desire - children should be wanted.
He continually puts you down (not ambitious enough, not trying hard enough to save for a deposit - are you saving more than half the amount he is every month? Given you are earning half what he is if you are you're actually doing BETTER at saving than he is!)
And again as several pp have said is leading you on.
I'm no romantic (sbxh cheated) but for legal and practical and economic reasons with the current legislation I'd caution anyone against having children or making a significant investment with another person without being married.
My divorce was hell, BUT it gave me financial and legal protection (some of which over 10 years later I suspect may be about to surprise sbxh). It made sorting the finances easier and fairer.
IF you stay with him I think you should make damn sure its on your terms.
And I don't think he was joking at all! I think he's backtracking. He's got a cushy deal at the moment.