All three. Smoother feel, softer tone, last for ages or forever depending on taste.
I use Chromes on my P Bass, had a set on for 18 months and I can’t see that changing. Chromes have a nice bright edge to them, and are a peach once they’ve aged.
But in your position, I’d also consider the EB Cobalt Flatwounds, which I used on an old PJ of mine and now have on my Stingray Special. They are technically flats, but lean more towards the brightness of rounds. As said in an earlier post, flats can start bright, but these have other properties of rounds that’s a nice touch too.