If I had a power of effecting people's minds and habits I would suggest to live the surnames and geographical names alone; no inflection please.
bad idea -
a jadę do Rzym, jadę do Moskwa, - no regulation will make people talk like that boletus
jeśli
spotkałem się z Jackiem Dukajem to dlaczego
spotkałem się z Jack Straw zamiast
z Jackiem Straw -
btw - if you have a name like Pat Robertson (which could be either male or female Polish declination can often show the gender
Spotkałem się z Patem Roberstonem. vs Spotkałem się z Pat Roberston. if you used nominal form for a male Pat Robertso many people would think you met a female eventually
and it is sometimes important to know the gender to use the correct grammatical forms that should reflect the gender
I've seen foreign womens' names declined both on polish internet pages and in print. In Poland.
some do get declined - Alicia Huggins, Alicii Huggins (gen, acc, loc, dat), z Alicią Huggins (inst.), Alicio Huggins (voc. however rare or strange even to the native speakers) - you should be able to see the pattern
Camilla Parker, Camilli Parker, Camillą Parker
Wiera £awrowa - dat Wierze £awrowej - gen Wiery £awrowej - acc Wierę £awrową loc Wierze £awrowej ins Wierą £awrową voc Wiero £awrowa
Martha Fonseca - acc Marthę Fonseca/e gen Marthy Fonseca/i dat Marcie Fonseca/e loc Marcie Fonseca/e ins Marthą Fonseca/ą voc Martho Fonseca