Added RSI filter. -> buy when MACD line is above the Signal line and RSI is lower than <75 for example to prevent buying tops or buy only oversold areas <40. Vice versa for shorts, buy only if RSI is above 50..70.
Leaving this settings default at max RSI 100 and min 0 'DOES NOT' apply any filters.
Another important thing to mention - strategy HOLDS buy and sell signals if MACD is above/under Signal line, to prevent missing crossovers when strategy switched to the better parameters. If you apply pyramding >2 you will see that it repeats signal every bar, this is how it has to be. You can apply RSI filters though and buy 3-5 times (pyramiding) when market was oversold and MACD crossed. Experiment.