Agreeing to forgo child maintenance

[Fuzzypinetree]

I'm pondering at the moment, so what do others think about not asking for child maintenance? (I can get my lawyer to draw up an agreement...)
The situation is that ex is a cheating arsehole, who left a few days before DC2 was born because he had to sleep with his colleague...
Since then, he's not paid maintenance. I've managed on my maternity pay for the past year and I'm now officially back at work (but it's the summer holidays, so I'm wfh). He's had notice that he's liable for child maintenance and that's currently all adding up until we go to court. In theory, I should be buying him out for 100k. However, the bank is beyond slow in getting things sorted and I will have to pay additional taxes if the house gets signed over to me after the divorce has gone through (I can file from next week).
I was considering offering that he signs the house over to me, doesn't get the 100k but wouldn't have to pay child maintenance going forward. (And I could be persuaded to drop the claim on the outstanding amount, which is now at about 10k.) By the time DC1 is 18, he'd have paid about 120k in child maintenance.
For him, it would mean that he has no financial responsibilities towards us or the house anymore. For me, it would mean not having to take on an additional loan and the divorce would go through much quicker.
Any thoughts? Is that a stupid proposal? (No point suggesting it to him if everyone thinks it's a dumb idea and he wouldn't go for it...)

Just read op is in a different country and didn’t say so (or which one). That would have been useful…

So no, we aren't having 50:50
Are you saying that if he wanted ot when the children are a bit older, and so did they, he couldn't get to court to request it? I very much doubt it. Thi gs can change a lot in 18 years.

Your proposal sounds good on the surface, but in reality, has too many shotfalls to be fair.

My sister did exactly this and the court signed it off straight away.

@notmypeasnotmyallotment your sisters ex was daft to agree it if they’re U.K.

It would be a sensible thing to do, and advantageous all round.

I considered suggesting something similar to my ex, but, I thought it through, and there was no way he'd have gone for it. They see the big number up front, and can't think ahead to the smaller numbers and hassle in the future.

You know your ex better - is he able to be logical about this? Or would he also just be blinded by the big up front number?

It’s really not sensible to the ex who loses out on certain cash now. Even less so in U.K. where after 12 months cms would still be awarded irrespective of any court/legal agreement.