Just a few remarks:
• A downside to stop-loss orders is price gaps. If a future’s price gaps past the stop price, the order triggers, and the future is sold (or bought) at the next available price, regardless of a sharp price move.
• Depending on which future you are trading the pricegap between placing order and execution can be different. ES is less volatile than NQ, so ES will give better fills. Pricegaps of 8-15 points are only possible at certain critical moments, but I have never seen a fill with a pricegap of 8-15 points in my fills.
• Stoploss versus stop limit order
A stop limit order will be only executed at the price of the limit order, or at a better price. So you are never sure that the order will be executed. So the best stop is a stoploss order.
• Latency is important, not teh 600-900 mbps that you mentioned.
Go to C:***\Documents\NinjaTrader 8\log. Find a date on which an order was executed and open it. In this file you can see the whole procedure and the exact time at which that step was executed. You will see how many ms it took to exectute the step. You are probably located in the Netherlands, so the order should be executed in 200-300 ms in normal market conditions. For ES the fills are in general between 0-2 ticks away from your stoploss order. For NQ the gap is in general wider.
• You use a laptop. Check if the settings are at maximum power, the default settings in general are at a lower level to save the battery. Check if sleepmode (slaapstand) is switched off completely.
• Simulation is just to give you an idea about the potential of your system. The prices at which orders are executed are FAKE. A simulation never knows what the real execution price will be. So the real test is to trade in real mode. Just take a very small position (with micro contracts it is not expensive) and see what happens. Only if these real live tests are successful you know what to expect more or less. Never take the simulation returns for real.
• I would test on MES, not MNQ, because the volatility is smaller. The fact that intraday margins for NQ and MNQ are double the amount from ES and MES, confirms my opinion. Better start small, as your risk less money. And if the system performs very well, you only need a few days extra before you will be a millionaire. 
• PM me if you need more help. I speak 4 languages, including your native language I think.