Finding Best Time to Scalp Major Pair

I start my job again making trading system for major pair. This system is still working on a particular clock hour. For that I tried to dig up from some other popular EA, see the tendency at any hour they work.
I find generally brief EA is working on a range of time shorter than the EA is working on Cross Pair. This makes the number of trades executed may be very little. This coupled with the fact that they generally only work 4 days a week. The effect recovery factor will be a long time, when the EA suffering draw down.
Interestingly most of the EA is able to work in more than one pair at a time, either by using the same variable or different. Unfortunately one of the fundamental weaknesses that are owned by the Meta Trader is that we can not do backtest on more than one pair. So we can not determine whether it is more profitable or not. Diversification effects may not work properly as expected.
As a preliminary conclusion, I see that most of us will get a good backtest results if we restrict the EA to work on the 21-23 or 20-23 hours GMT +2. This is not foreign to me, because when I make VS_EurCHF, for the pair EURUSD, the profit factor increases if the trading time is limited to 20-1 GMT +2.
I tend to wish to make my EA is able to work as well as with the Cross pair. However, until now, I must admit, that forced to work like that cause suffering Account large draw down. Until now I was thinking to try some exit strategy. With a small amount of trade, should be made to maximize any existing trade instead of just scalp it.