While regtesting with [bitcoin-spock](https://github.com/msgilligan/bitcoin-spock) I noticed at some point the transaction creation via `sendtoaddress -> CreateTransaction()` fails, because the created transaction is larger than `MAX_STANDARD_TX_SIZE`.

During the process a lot of raw transactions are created, which have smallish outputs and when then using `sendtoaddress`, it appears to attempt to create a transaction that spends too many of those dust-ish outputs.

The transaction to create does not have many outputs, but it looks like it's caused by the coin selection, which selects too many inputs. Testing was done with a 0.9 branch, but on the first glimpse I believe this issue is as well be present in 0.10. If this is a known issue, and if there is already a guard against this behavior, I'd be happy about a hint.

Sorry in advance, I do not have a test script to reproduce this issue in an isolated manner. A potential fix would probably require to adjust the coin selection, so that it selects a combination of coins, which, in addition to the size of the rest of the transaction, is still smaller than the limit.

{
    for (auto& [type, vec] : coins) {
        auto remove_it = std::remove_if(vec.begin(), vec.end(), [&](const COutput& coin) {
            
            if (coins_to_remove.count(coin.outpoint) == 0) return false;
            
            total_amount -= coin.txout.nValue;
            if (coin.HasEffectiveValue()) total_effective_amount = *total_effective_amount - coin.GetEffectiveValue();
            return true;
        });
        vec.erase(remove_it, vec.end());
    }
}
void CoinsResult::Shuffle(FastRandomContext& rng_fast)
{
    for (auto& it : coins) {
        ::Shuffle(it.second.begin(), it.second.end(), rng_fast);
    }
}
void CoinsResult::Add(OutputType type, const COutput& out)
{
    coins[type].emplace_back(out);
    total_amount += out.txout.nValue;
    if (out.HasEffectiveValue()) {
        total_effective_amount = total_effective_amount.has_value() ?
                *total_effective_amount + out.GetEffectiveValue() : out.GetEffectiveValue();
    }
}
static OutputType GetOutputType(TxoutType type, bool is_from_p2sh)