one issue is having failures red flags that will likely be easy to glean at a glance on your app, coupled with the fact that most docs in the US are likely not familiar enough with the UK training system to understand the positive factors you are saying sort of redeem you
I can't speak for PDs and how familiar some might be, but unless it's an IMG friendly program (you can track this down online usually) then I really wouldn't expect them to be at all, and even if it's an IMG friendly program that still doesn't mean that they will be able to appreciate any app in a practical sense that isn't just on stellar terms prima facie
for example most aren't going to be familiar enough with the UK to know that you are in a top 5 out of 10 med school (no offense, I don't think being in top 50% of med schools will be impressive when there are so few, or even here in the states with over 150+ schools)
I don't mean to discourage you. You are right, working hard, getting excellent LORs, applying broadly, will help. Networking and getting some US training experience and letters would be good too.
It's true that I think those who have trained in a first world English speaking country have the best chance of IMGs, like Canada, Australia, UK, but that said it's still hard and there are tons of those candidate and US ones that are red-flag free and still find it hard to get here.
Anyway, I don't think hope is lost, but I would definitely pursue any options you have for training in and out of the US.