Askaboutmoney is not really designed to answer complex tax planning points like this. You need to pay a professional tax advisor who can take all your circumstances into account.
But as a general point, and I am not a tax specialist...
If you draw down only enough profits now to use up your 20% tax band, the company will pay Corporation Tax on the profits left in the company.
I think that if the profits in the company are from investments, they will be taxed at 25%.
Then when you draw out the profits as salary, they will be taxed at your top tax rate.
Unless you wind up the company and then you will pay 33% CGT on the assets - assuming the initial share capital was zero.
So, it seems much cleaner for you to distribute all the profits either as salary or pension contributions.
Brendan