I've spent a lot of time in the US recently and it's normalised my accent a lot. It's become undefinable. People back home tell me I don't sound like them when I speak, but that I don't sound quite American either.
Americans make fun of how I pronounce certain words (which actually helps a lot in normalising my accent), but they can't place the accent either. Nobody guesses that I'm slavic, a lot of people ask if I'm Brazilian or from some random European country.
A large part of the confusion probably stems from the fact I use colloquialisms and even colloquial speech patterns, like, correctly.
With prolonged stays in the US my accent is going to normalise further, but I think that getting completely rid of it would require some sort of accent coach. So far the only motivation for doing so is that being told "Wow your English is so good!" is getting annoying. I was proud when people told me that ten years ago, but it feels silly now.
But a big benefit of maintaining my foreigner status is the freedom it affords me. I can use British slang, Aussie slang, East coast slang, West coast slang, even Canadian slang and nobody minds or finds it odd. Whereas if I sounded like somebody who grew up in California and used a British turn of phrase, it would sound hella weird.
And, obviously, I feel a certain level of smugness when I use British words that Americans don't understand because then I get to call them plebes and mock them with my larger vocabulary. (Americans get really upset when a foreigner is better at something than they are, it's funny)