Man, that is a tough one. Our parish has a large number of believers who speak English, a larger number of believers who speak Spanish, and a number of believers substantially smaller than either of the two groups mentioned previously who speak both languages. You can imagine what happens at the bilingual liturgies on special days, such as Christmas mass at midnight, Ash Wednesday, Holy Thursday, Easter Vigil, and last year at a special Jubilee mass. Then there are the separate choirs, whose members and leaders get along with varying success which is kind of a shame. On the other hand, the liturgy in two languages ultimately leaves something to be desired for all but the truly bilingual or truly openminded.
Some celebrants are better at juggling the two languages than others.
I'm not sure what the solution is perhaps missalettes or liturgical aids in two languages, so at least those whose language is not at the moment being used can follow along. As I said before, the problem is a tough one. I see no reason to equivocate, and certainly consecration is no more valid because it's executed in English. You're right, some celebrants personalize the liturgy too much, especially if they use it as a vehicle to promote or to sustain the life of imperialistic, ethnic, or linguistic prejudices. Man, that is a tough one.