Here is a book that is due to be published shortly that might help answer some of your questions related to trading and the tax implications.
http://books.global-investor.com/books/19974.htm?ginPtrCode=10170&identifier=4361667b2e6c048fcdacfdd32c677c34
I can't review it as it hasn't been published yet but I have it on order so will update when I have it.
Some people have mentioned offshoring as a way of minimising taxes. My understanding of this is that unless you actually
reside offshore, yes all profits will roll up gross of tax. However, when those funds are repatriated onshore, then the usual tax will be payable. So unless you intend to spend long periods out of the country, the benefits are minimal (imho).
The offshore 'loophole' was closed some years ago. It can still have benefits, particularly for mitigating inheritance tax in the form of offshore bonds, which can both save CGT and income tax, but I can't see any benefit for the trader.
Hope this is of some use.