Please disregard other posters advice, as they are not familiar with the A-level system.
(1) Your As are excellent and with AA*B you should be able to get in.
(2) You DO NOT need to send in the SAT or ACT. Disregard other posters advice in this area. NYU accepts A-levels and A-level predictions as sufficient to meet the standardized testing requirement, as A levels are standardized tests.
GCSE with AS-level and A-level are a sufficient substitute for the testing requirement for admissions.
I would say you have excellent chances of admission - assuming your essays and recommendations are good - especially if you apply ED.