am I going overkill with a $3-4k cartridge given my tone arm/tt?
Possibly
I’m pretty happy with the sound I’m getting currently but want to stay away from a cartridge that’s too forward sounding. I love the high end detail I’m getting from the diamond tweeters of my B&W 805d3’s but feel it can get a little bright at times.
The Kiseki is much smoother than the Hana cartridges, but from my personal experience they are not particularly resolving given the price.
I would have a look at the Soundsmith range - the Soundsmith MI cartridges are incredibly smooth and resolving - they should be a good match for the B&W's with the Diamond tweeters. You can select output and compliance to suit your arm and phono stage. Anything from US$2k should be an upgrade over the Hana.