Concept of ops then.
Get a second job and pay yourself a huge divi, if you fancy a decent sized family then don't hang about (you've two years), practice telling your kids how the new living wage means they needn't (mustn't!) go to uni, and sell that buy to let. The 40% threshold to £43,000 works out at only about a 1.5% increased benefit, so quietly shelve that secondary duty too.
I knew you and I think alike!
I call that neo-bilkoism (after Sgt Bilko)
BTW, It's pretty much the same thought process that did for the Roman Empire.