Some comments from @sipa in #12702.

___

Yes, I think `importmulti` is superior in every way, except:
* Slightly less convenient to use (it requires redundant information, as you have to explicitly state what you want to import, and then give the keys/... to enable that).
* ~Doesn't support P2SH-P2WPKH yet~. Added in #14454

The latter can be fixed by just adding support for that case. The former can be improved by adding 'default' cases (e.g. if you prove a WIF private key, it can permit omitting the address, ...).

"\nVerify the signature\n"
            + HelpExampleCli("verifymessage", "\"1D1ZrZNe3JUo7ZycKEYQQiQAWd9y54F4XX\" \"signature\" \"my message\"") +
            "\nAs a JSON-RPC call\n"
            + HelpExampleRpc("signmessage", "\"1D1ZrZNe3JUo7ZycKEYQQiQAWd9y54F4XX\", \"my message\"")
        );
    LOCK2(cs_main, pwallet->cs_wallet);
    EnsureWalletIsUnlocked(pwallet);
    std::string strAddress = request.params[0].get_str();
    std::string strMessage = request.params[1].get_str();
    CTxDestination dest = DecodeDestination(strAddress);
    if (!IsValidDestination(dest)) {
        throw JSONRPCError(RPC_TYPE_ERROR, "Invalid address");
    }
    const CKeyID *keyID = boost::get<CKeyID>(&dest);
    if (!keyID) {
        throw JSONRPCError(RPC_TYPE_ERROR, "Address does not refer to key");
    }
    CKey key;
    if (!pwallet->GetKey(*keyID, key)) {
        throw JSONRPCError(RPC_WALLET_ERROR, "Private key not available");
    }
    CHashWriter ss(SER_GETHASH, 0);
    ss << strMessageMagic;
    ss << strMessage;
    std::vector<unsigned char> vchSig;
    if (!key.SignCompact(ss.GetHash(), vchSig))
        throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Sign failed");
    return EncodeBase64(vchSig.data(), vchSig.size());
}
static UniValue getreceivedbyaddress(const JSONRPCRequest& request)