Delegation program relies on submissions that the node prepares using uptime snark worker.

In the worst case, uptime snark worker will attempt to snarkify an extra-large transaction, which takes ~6m on Berkeley and would be worse on Mesa.

Requirements of delegation program could be satisfied with a simpler design. I suggest to prove the last segment of the last transaction of a block, and it is enough to prove node's online, while takes 10-30s at most..