You get more flexibility, but managing weights means thinking about strategy — things like impermanent loss and APR changes. Arbitrary Provision is also available, which gives you more flexibility when adding liquidity to V2 pools (you can add liquidity using just one of the two tokens; the interface routes the necessary swap under the hood).
One thing to keep in mind on cost: more complex pool configurations may involve more contracts or hops in the swap route, which can add up in network fees. For very small swap amounts, the fees can eat a meaningful portion of the swap — so WCPI is most effective when you have a deliberate liquidity strategy rather than ad-hoc micro-swaps.
Review your strategy carefully before committing.