Your GCSEs are perfect. Your A Level target grades are great, so make sure you achieve them at least. EPQ will give you an edge especially in terms of personal statement and interview. UCL like EPQ a lot. Take it easy on the UCAT for now. You only need about 5 weeks of revision. More is NOT better. People burn out so easily when preparing for the UCAT, even the students that are used to working ridiculously hard for school exams. The UCAT is a mind game and needs to be revised for tactfully, so don't worry about it yet.
You seem very interested in research (like me
), so universities like Cambridge, Oxford, Imperial and UCL would be idea. There are probably more, but those are the ones i can name off the top of my head. You should make your uni choices AFTER getting your UCAT result. It can hugely alter your decisions. I would not advise applying to 3 BMAT unis, unless your UCAT is too low to apply to any UCAT unis. This is because you sit your BMAT in October/November, which is AFTER you submit your UCAS application. Also do keep in mind that some Scottish unis strongly prioritise scottish applicants over english ones.
Other than oxbridge, 'risk' only applies until you get to interview. Once you have an interview, you have to do well regardless of the uni. After you start BMAT prep, if it's feeling good, totally apply to two out of Oxford, Imperial, UCL. If it isn't looking too good, apply to one of either UCL or Imperial, as their cut offs are lower than Oxford. Don't know much about St Andrews, but if you do very well in your UCAT, King's College London is a very good option, especially considering your GCSEs. Since you're interested in London unis, St George's could be a good safety choice.
For now though, don't worry about this too much. Focus on your predicted grades and EPQ, as well as doing volunteering and work experience. Reflect as much as you can. Once you've done your UCAT, you'll be able to make these decisions. I'm applying this year, so if you have any questions, feel free to PM me. I hope this helps