TXs should be prioritized based on a well-defined strategy

[autholykos]

Describe what you want implemented
A strategy for mempool prioritization based on transaction fees should be introduced. This also involves a (probably custom made) rate limiter that would prioritize transactions with higher fees

Describe "Why" this is needed
We want to give precedence to some transactions based on a good strategy. Moreover, since the introduction of rate limiting, there is an opportunity for propagation of transactions with higher fees first

Describe alternatives you've considered

• Tipping the block generators
• Prioritize based on higher gas price
• Calculate the range of the previously spent tx divided per contract

Wrt the rate limiting we can do nothing and delegate prioritization of transaction execution to the recipient queue. It is actually unclear which approach is the most desirable.

Additional context
Originally posted by @autholykos in #1238 (comment)

[autholykos]

The strategy should also keep into consideration eventual flooding attacks based on burst of invalid transactions. In this case, we should make sure that valid transactions in the Mempool are not dropped nor affected

[fed-franz]

Should we close this? @herr-seppia
We already ARE prioritizing txs based on higher-gas-price strategy.