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, ...).

if (fUnlock && !is_locked) {
            throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid parameter, expected locked output");
        }
        if (!fUnlock && is_locked) {
            throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid parameter, output already locked");
        }
        outputs.push_back(outpt);
    }
    
    for (const COutPoint& outpt : outputs) {
        if (fUnlock) pwallet->UnlockCoin(outpt);
        else pwallet->LockCoin(outpt);
    }
    return true;
}
static UniValue listlockunspent(const JSONRPCRequest& request)
{
    std::shared_ptr<CWallet> const wallet = GetWalletForJSONRPCRequest(request);
    CWallet* const pwallet = wallet.get();
    if (!EnsureWalletIsAvailable(pwallet, request.fHelp)) {
        return NullUniValue;
    }
    if (request.fHelp || request.params.size() > 0)
        throw std::runtime_error(
            "listlockunspent\n"
            "\nReturns list of temporarily unspendable outputs.\n"
            "See the lockunspent call to lock and unlock transactions for spending.\n"
            "\nResult:\n"
            "[\n"
            "  {\n"