Strength expert advisor

My new idea is a multi-currency expert advisor.
It uses a group of selected currencies in order to estimate the strength of two single currencies.
If I will be able to know the currency's strength I can use it for trading.
Since the EURUSD has a low spread it would be my first choice.
I would like to estimate the strength of the EUR and the strength of the USD.
Each strength would be in the scale of 0 to 1. 1 is the strongest and 0 is the weakest.
As a start if the EUR's strength is over 0.8 and USD's strength is less than 0.2 then it should go long and vice verse for short. Trades are closed upon reverse signals.
It's a simple strategy with a big problem: it cannot be back tested using the Metatrader since it doesn't support mufti-currency EA's. For that purpose I needed a VPS.
For my needs a 1GHz CPU with 1GB RAM will do.
It's important that it will be alive 24/7 without any connection problems.
I used a money management system in the EA. The take profit is a factor of the loss, and the loss is defined as a risk in % of the account's equity.
I ran it for 24 hours on a demo account and the results were amazing:

• A lot of trades were made
• The profit factor was between 1.5-2

After a week and a half the demo account earned 15%. 

115 trades with a profit factor of 1.66.

That's a good start for the EA I'm looking for!