You really need to get professional advice, this area has obliviously become a huge growth area for tax specialists, and while not hugely complex there are a lot of tax benefits that can be missed if not handled correctly.
You also have to realise there is not just income tax implications here but also CGT and CAT & SD, mortgage interest relief, allowances.
Some of the basic points are as follows:
You can use maintenance payments as an offset against your gross income if you have a Legal separation or divorced (but not if just separated you must be legally separated). This payment will then be taxed in the hands of the recipient. Very large benefit if you are saying a marginal rate payer and the other spouse is a standard rate payer.
Payments to children no allowances, so you increase payment to spouse to account for children thereby receiving tax benefit.
No CGT between spouses but if assets are passed under a legal separation or divorce there will be no CGT otherwise afterwards there will be. So this is why you will see the t/F of assets such as houses at this time.
I am by no means a specialist in this area but I do know there are significant tax savings to be made if handled correctly so take professional advice you will get a list of tax specialists in your area on the AITI website.