You might think people are recommending ChipMixer because they are getting paid for the signature campaigns but from my perspective, you should be using them as they're around for a long time and wouldn't run away with your money. I'm not quite sure how much of anonymity you'd get after using their service but that's something I'll leave someone else to answer. Converting to Monero and back to BTC isn't really mixing your coins the right way.
every method has drawbacks. chipmixer has superior liquidity and excellent tumbling procedure but you must trust them 1. not to keep logs and 2. to custody your funds while using it. in fact, the longer you hold their generated private keys (trusting them not to steal them),
the better the privacy guarantees:You are free to sweep it yourself, ask us to send it to your address or keep it on chip for a while. Only the last option keeps your funds vunerable to our dishonesty, but it also extends your privacy. If you sweep funds from chip in first 12h after your input, you receive same privacy as you would get from standard mixer. If you trust us (as you already did when you sent coins into mixer) and spend chip when you need it, then you achive maximum privacy you can get.
theymos made a guide about mixing earlier this year and
swapping to monero was his #2 choice. it's probably the most expensive option if using instant exchangers.
one drawback of wasabi wallet is that it's blatantly obvious you are using a coinjoin because it enforces a 100-anonymity set. another is the ~0.1BTC minimum. it's definitely cheaper than swapping to monero though.