You do know that a FTA usually comes with a supra national body which rules in case of trade disputes?
The EU is loosely termed a supranational union as its a multinational political entity, but no third country is going to grant the EU a non partial judicial system such as the ECJ to oversee FTA dispute, The standards in an agreement will have as a minimum the highest standards of legitimacy, transparency and neutrality
There are three types of dispute settlement used in EU trade policy:
Dispute settlement at the World Trade Organisation,
Resolving differences between States under international trade agreements &
Investment dispute settlement
Thus how is the UK not tied to EU regulation when a FTA with the EU will contain regulation stipulating the UK has to follow some EU rulings?
Yes an FTA has to make allowance follow some rules of the EU and vice versa, As an example both participates in the agreement will have to follow the guidelines for the importation of foodstuffs for biosecurity needs which is vastly different from have influence in enacting sovereign laws of the nation, which as a member of the EU one has to do.
The only way to get complete sovereignty is by having no FTA. However, this is something you don't propose (at least in the end state).
Thus it's indeed arrogant assuming that the EU will not demand the UK following (the majority of ) its trade rules and ensures that there is a body which can enforce this regulation upon the UK. The EU isn't stupid and if you've followed TTIP a little bit, you would know that the EU, and more important its members, will never allow a FTA which doesn't secure its interest legally (the composition and responsibilities of the resolution body was one of the major breaking points).
You can demand all you want in an FTA, but if the EU stipulates rules and measures not in one own interest an agreement will never be reached nor should it be, There was no deal between Australia-US FTA initially as it was not in the interest of Australia
Or do you define "sovereignty" by "not having to follow ECJ rulings"? If so, why are you objecting against May's proposal, in which the trade dispute body has a different name.
The ECJ will not be an impartial and neutral body, its would be like give the Supreme Court of the United States power to decide disputes on an FTA between the EU-US(if one ever happens) are you willing to do that?
A FTA is an outcome of negotiations whereby usually the bigger party gets more than the smaller party. Yes one can have respect, but a FTA is pure business and politics. And you really believe that, for example the US. will not impose a resolution board when signing a FTA with the UK? Come on, they're not stupid (again see TTIP).
look at Australia -US FTA, Australia walked away as it was not in their best interest, you can demand but just expect a no in return. AU also walked away from the TPP
Your implying that a resolution board will be stacked in the US favour, one only has to look at CETA on how this works at an Appellate Tribunal, and is not conducted by the ECJ and will function in a similar way to the WTO Appellate Body
An arbitral tribunal is still comprised of three arbitrators. However, those arbitrators are chosen from a roster of fifteen people that is created by Canada and the European Union. This roster will be populated as follows: five members who are Canadian nationals, five members who are EU nationals, and five members who are nationals of non-Party third countries. A three-person division hearing a dispute will be composed of one person from each pool: i.e., one Canadian national, one EU national, and one national from a third country. The third country national will chair the division. When a division is formed to hear a dispute, the President of the Tribunal will appoint the members on a rotation basis, ensuring that the composition of each division is random and unpredictable, while giving equal opportunity to all Members of the Tribunal to serve. A person appointed to the roster will serve as a member for a term of five years.