3) To negotiate better-than-average trade deals
You're lying to yourself if you think than one single country can negotiate better trade deals than a block of 28 countries. When negotiating it matters how powerful you are compared to the other party, and the EU is stronger than the UK on it's own.
And regarding your other points: We'll see about 'membership fees' and controlling immigration when you are going to ask to get access to the EU market. You can't have the benefits without the obligations. If you believe the BS that Farage and Johnson promised then I feel sorry for you.