[Agata]

I find that our cameras see stuff we often don't have the eye for. Polarizer should work as it would allow you to expose the background better and make the sky a more vibrant blue. Just make sure you use get the wb right otherwise it'll look a bit weird, at least it did in my case.

Try taking the photos at a different time of day too, mornings are best for this because the air is cooler and the smog levels are lower.