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 (wallet.IsLocked()) {
        throw JSONRPCError(RPC_WALLET_UNLOCK_NEEDED, "Error: Please enter the wallet passphrase with walletpassphrase first.");
    }
}
WalletContext& EnsureWalletContext(const std::any& context)
{
    auto wallet_context = util::AnyPtr<WalletContext>(context);
    if (!wallet_context) {
        throw JSONRPCError(RPC_INTERNAL_ERROR, "Wallet context not found");
    }
    return *wallet_context;
}
LegacyScriptPubKeyMan& EnsureLegacyScriptPubKeyMan(CWallet& wallet, bool also_create)
{
    LegacyScriptPubKeyMan* spk_man = wallet.GetLegacyScriptPubKeyMan();
    if (!spk_man && also_create) {
        spk_man = wallet.GetOrCreateLegacyScriptPubKeyMan();
    }
    if (!spk_man) {
        throw JSONRPCError(RPC_WALLET_ERROR, "This type of wallet does not support this command");
    }
    return *spk_man;
}
static void WalletTxToJSON(interfaces::Chain& chain, const CWalletTx& wtx, UniValue& entry)