While working on this PR https://github.com/bitcoin/bitcoin/pull/18570 I ran into a bit confusing situation where in one function a **CWallet reference** was expected while two others dealt with **CWallet pointers**. My initial reaction was: `let's harmonize them by making them references`. However, not being part of the PR itself I did't change anything and completed the PR first.

Now, after having analyzed the `rpcwallet.cpp` code I came to the conclusion that:

* converting them all into references is not the solution as they're originally **shared_ptr**s
* but also: there is no (visible) reason why every RPC function should begin like this:

```cpp
std::shared_ptr<CWallet> const pwallet = GetWalletForJSONRPCRequest(request);
const CWallet* const pwallet = wallet.get();
```

This clearly defeats the purpose of shared pointers for no obvious reason. *Maybe I am missing something?*

In my (unpublished) [code changes](https://github.com/brakmic/bitcoin/commit/0b3ee615491edf6f542631bf6ae6f72eac406550) all raw pointers got replaced with **shared_ptr**s but kept their original names (that is, *pwallet*). In the end, they're pointers too, so the most of the original code remained untouched.

However, some of the helper functions couldn't be changed because external code is accessing them and I didn't want to make this task "virulent". So I introduced new ("Ref") variants that expect **shared_ptr** parameters, namely: 

```cpp
void EnsureWalletRefIsUnlocked(const std::shared_ptr<CWallet>);
bool EnsureWalletRefIsAvailable(const std::shared_ptr<CWallet>, bool avoidException);
```

I have tested the code, with python and boost-tests, and could not find any errors. 
But before opening a PR I would like to open a discussion about this. 

Is there any reason to keep on working with raw pointers when every function call actually begins with *shared_ptr*s?

Regards,
if (rbfState == RBFTransactionState::UNKNOWN)
            rbfStatus = "unknown";
        else if (rbfState == RBFTransactionState::REPLACEABLE_BIP125)
            rbfStatus = "yes";
    }
    entry.pushKV("bip125-replaceable", rbfStatus);
    for (const std::pair<const std::string, std::string>& item : wtx.mapValue)
        entry.pushKV(item.first, item.second);
}
static std::string LabelFromValue(const UniValue& value)
{
    std::string label = value.get_str();
    if (label == "*")
        throw JSONRPCError(RPC_WALLET_INVALID_LABEL_NAME, "Invalid label name");
    return label;
}
/**
 * Update coin control with fee estimation based on the given parameters
 *
 * @param[in]     wallet            Wallet reference
 * @param[in,out] cc                Coin control to be updated
 * @param[in]     conf_target       UniValue integer; confirmation target in blocks, values between 1 and 1008 are valid per policy/fees.h;
 * @param[in]     estimate_mode     UniValue string; fee estimation mode, valid values are "unset", "economical" or "conservative";
 * @param[in]     fee_rate          UniValue real; fee rate in sat/vB;
 *                                      if present, both conf_target and estimate_mode must either be null, or "unset"
 * @param[in]     override_min_fee  bool; whether to set fOverrideFeeRate to true to disable minimum fee rate checks and instead
 *                                      verify only that fee_rate is greater than 0
 * @throws a JSONRPCError if conf_target, estimate_mode, or fee_rate contain invalid values or are in conflict
 */
static void SetFeeEstimateMode(const CWallet& wallet, CCoinControl& cc, const UniValue& conf_target, const UniValue& estimate_mode, const UniValue& fee_rate, bool override_min_fee)