It outlines an algorithmic approach to manage and distribute transaction fees more efficiently across multiple transactions, ensuring that the wallet maintains enough available coins for future transactions. The process involves identifying the optimal set of funding inputs and change outputs for a given spend amount and desired fee rate, with the ultimate goal of minimizing the overall cost of transactions.

The algorithm starts by categorizing available coins into target buckets, each defined by the user with specific attributes such as start and end satoshis and a target count of UTXOs (Unspent Transaction Outputs). Based on the current state of these buckets and pending transactions, the algorithm computes the capacity of each bucket to determine which one has the least capacity and is in need of refill. If the capacity of the least full bucket is significantly low or if the current fee rate falls below a predefined threshold, the algorithm opts to create change outputs to replenish the target buckets.

Coin selection plays a crucial role in this process. The algorithm selects coins that not only cover the spend amount but also allow for the creation of change outputs, if necessary. These change outputs are then strategically split among the target buckets to ensure they are refilled adequately. This splitting is done based on the capacity needs of the buckets, starting with the most depleted ones, and considering the cost associated with creating new outputs.

In essence, this proposal introduces a sophisticated method for managing liquidity in a cryptocurrency wallet. By dynamically adjusting to the wallet's current state and the network's fee environment, it seeks to optimize transaction costs while ensuring sufficient liquidity is maintained for future transactions. The use of target buckets and strategic coin selection and change distribution presents a proactive approach to wallet management and cost minimization.