If your wife can do the 'administrative' work, and you share the family finances, there's no reason why you can't pay her a salary for that administrative work which would allow the family to benefit from that income with only 33% tax (22% income tax, 11% NIC) instead of the 41% (40% income tax 1% NIC).
On the other hand, I would suggest recruiting the services of an accountant to discuss the possibility of setting up a company with both you and your wife, and paying dividends instead of salary., since these are just 10% for the wife's "share" and 32�% for your 'share'