It's just speculation, not a proposal or going through as law.
The cap of £23k is still too high, more could be gained by lowering it. Benefits should not be paying more than a lot of people earn by working.
Child benefit stopping after two children is also not the end of the world, it's a parents job to provide for their children.
DLA is not means tested so it can be claimed by everyone regardless of household income. Should it be taxed, not really as its state money in the first place. Just freeze it for a few years if savings are needed rather than over complicate things.
CA is dependant upon household income, therefore rolling it in with UC makes sense. So much has been spent on the system it should be used to its maximum potential.
They could leave CA and DLA alone and simply remove IS for lone parents after a child reaches age 1 (with no new claim for further children). That would save more and make it equal for all new mums. Either you work or your stay home at no cost to the state.