What are the most balanced relatively neutral cartridges at each price level ?

Under $500? Ortofon 2m Bronze or Hana EH.

Under $1000? Ortofon 2m Black or Hana SL or SH Mk 2. Also, The Hana S Mk 2 carts are probably the best overall value available. 

Under $2000? Hana SL or SH, 

Over $2000? Hana Umami Blue ($2500) or Red ($3950)

Over $4000? Honestly, not sure why you'd need to go there.

At level 2, $1-3K, I have a Koetsu

At level 4, $5K+, I have a Koetsu Onyx and a Koetsu Leopard. 
 

Koetsu is not known for its neutrality, but of the three, the Leopard is most neutral. 

level 1 - up to$1k. - Shure V15vxmr

level 2 - up to $3. - Shure V15vxmr

level 3 - up to $5k. - Shure V15vxmr

level 4. - any price. - Shake Streamliner

Question: if a balanced and neutral cartridge was available in the lower price range, why would anyone pay more for one? (I suppose cynics would say for bragging rights.)

Seriously, if a cartridge is balanced and neutral buy it. My view is that there is probably no perfectly balanced and neutral cartridge, merely approximations that get more expensive as they asymptotically approach.

My solution is to enjoy the sound of each cartridge. I can tell which one I am listening to, and I like the choice of which to use when I select an LP.