Methods (e.g. `eth_call`, `eth_getStorageAt`) don't take transactionIndex, only blockNumber

I don't know how hard this would be for implementers to support, but it would be nice to be able to simulate after e.g. the second transaction in a block.

Workaround is for the user to handle it: make a mainnet fork at height N, download block N+1, and then replay the first k transactions before doing analysis.

Well, maybe it could be a non-standard/optional feature like how some providers have nonstandard trace_* and debug_* methods.