I wondered if I could be self emploted as a consultant or possibly even as a Director (if I were to buy a token shareholding if the company were willing)? and if this could work out better from a tax perspective?
You cannot choose your employment status to suit yourself. "Consultant" means all manner of things, and it is not a magic word which makes someone self employed. A "self employed director" is almost always an oxymoron. A director is an office holder, and a director must almost always be paid as an employee (i.e. PAYE income tax and NICs). There are very few exceptions, and on the basis of the information provided I would agree with the company's accountant that you should be treated as an employee. Indicators - hourly pay, full-time work, no other clients, no obvious financial risk, no mention of own tools/equipment being used, part & parcel of the organisation, possible mutuality of obligation, no mention of provision of a substitute worker being possible or having happened.