I agree, on the EU election.
It could work in other elections, but they would have to make the constituencies bigger so they were multi seat. Works best where you have at least 4 seats per constituency i think. One benefit is it might smooth out the boundary moving a bit that labour and the conservatives like to partake in whenever they are in power.
Not using it for the EU election is fairly ridiculous seeing the size of the constituencies and the fact they are already set out as multi seat. I presume the only reason they don't is they think we are too stupid to understand?