Would it be completely unreasonable to allow `fundrawtransaction` to use unsafe outputs?

I understand this means the resulting transaction may be invalidated whenever the unsafe output I'm relying one disappears (e.g. because the transaction that produced it was RBF-ed) but in my case that's ok, I'll react to that and re-publish the tree of child transactions accordingly.

But let me know if you think that's too much of a footgun for users, in that case I'll architect my solution differently.
{
    if (IsWalletFlagSet(WALLET_FLAG_DESCRIPTORS)) {
        return nullptr;
    }
     Legacy s only have one ScriptPubKeyMan which is a LegacyScriptPubKeyMan.
     Everything in m_internal_spk_managers and m_external_spk_managers point to the same legacyScriptPubKeyMan.
    auto it = m_internal_spk_managers.find(OutputType::LEGACY);
    if (it == m_internal_spk_managers.end()) return nullptr;
    return dynamic_cast<LegacyScriptPubKeyMan*>(it->second);
}
LegacyScriptPubKeyMan* CWallet::GetOrCreateLegacyScriptPubKeyMan()
{
    SetupLegacyScriptPubKeyMan();
    return GetLegacyScriptPubKeyMan();
}
void CWallet::SetupLegacyScriptPubKeyMan()
{
    if (!m_internal_spk_managers.empty() || !m_external_spk_managers.empty() || !m_spk_managers.empty() || IsWalletFlagSet(WALLET_FLAG_DESCRIPTORS)) {
        return;
    }
    auto spk_manager = std::unique_ptr<ScriptPubKeyMan>(new LegacyScriptPubKeyMan(*this));
    for (const auto& type : OUTPUT_TYPES) {
        m_internal_spk_managers[type] = spk_manager.get();
        m_external_spk_managers[type] = spk_manager.get();
    }
    m_spk_managers[spk_manager->GetID()] = std::move(spk_manager);
}
const CKeyingMaterial& CWallet::GetEncryptionKey() const