Thank you all for your responses and for pointing out that I need 2555, not the EZ form. Nun's link led to an excellent summary of why FEIE doesn't help us in the UK.
I'll look at my numbers and determine what happens with FEIE + FTC vs FTC only. I hate attaching explanations, but I'd need to do that with first option since 2555 asks for details of original visa, whereas 2555-EZ simply asks when you arrived. I came here when I was 4, a dependent of father on work permit, later gaining ILR & UK citizenship.
I've been hesitant to revoke the FEIE for two reasons: (1) if I drop below the limit in future, I can simply file 2555-EZ and (2) the (probably delusional) thought that we'll return to the good old days when "excluded" meant "excluded", with passive income being taxed at lower rate.
Isn't it frustruating that income can be just above FEIE because of the exchange rate, something irrelevant if you're paid in Sterling and spend it all outside US?