Just go with the Polks; the S series sounds fine. From what I can gather, you are trying to build out a multi channel system and the Polks with be just fine for that. At under a grand with the need for white and visually appealing there won’t be a ton of options. What are you planning to do about a sub? If you aren’t going with a sub you will want towers as mains to get any real bass output.
Modern Polks usually aren’t on recommended lists (E.g. Stereophile) because they are consumer grade and not really in the considersation set of most audiophiles. Not to say they sound bad or anything its more that they are too inexpensive to be taken seriously. This is changing somewhat with their recent Legend series. Some folks here are spending more on a pair of cables or a phono cart than what all those Polks cost combined.
P.S. Polks (RT400s) were my first real speaker purchase back in the mid 90s as a teenager. I loved them and they are what got me into audio. I had to buy one at a time since I couldn’t afford a pair all at once; the sales guy helped me out since I was a kid making minimum wage and saving up for my system piece by piece. I still have those speakers and bust them out to enjoy them on occasion.