Can the seed protocol be altered in a manner such that the underlying architecture of the network (the blockchain) can be changed in the future?

If a node with sufficient computing resources will flood the network with many precomputed PoW transactions, how can the system mitigate this attack vector given the feeless architecture in Nano?

A directed acyclic graph has shown its technical implementation limits with regard to scalability and network activity; do you plan to remove in the near future the Coordinator node (including the milestone transactions)?

The whitepaper states that Radix is a new form of distributed ledger technology; it is not a blockchain, nor a directed acyclic graph. The question is, what is the foundational architecture used by Radix (the mathematical structure to store information, i.e. custom hashed link list for blockchain type DLTs)?