Hi mno,
I'll try to answer to your questions telling you my thoughts which are not regards you but the actual situation of the market. You have to consider that you will never be at the level of the HFTraders because of they usually have their own servers located inside the market and don't usually use external data vendor as we normal traders use. They usually rent servers directly form the CME or Eurex or FTSE and so on, so they have a direct access to market either for quotes and orders execution. Then it doesn't end here. They use very sophisticated protocols and trading systems which connect each other many markets and many instruments with a portfolio logical behaviour. With this logical operating environment and target, milliseconds make the difference, but for normal traders milliseconds is not so important for the order execution if you don't look for High Frequency trading operations in your trading.
Milliseconds is important to have good data to analyze the market, specially if you look for a good depth of market analisys regards volume.
Remember that you, as a retail trader , are forced to use retail data vendor and not professional data vendor which have monthly fee very very high for normal retail traders. You usually use retail broker and not direct access to the market to insert your order (usually from one to 5 or 6 at least and not hundreds in the same seconds in differents markets) and last but not least, usually you don't have a portfolio logical trading system which connects each market and different instruments in the same time as "Big Boys" as Goldman or others have.
So this way you have to make a question to yourself. Do you really need the power that these "Big Guys" have to insert your order and make your trading ? Do you have the money to stay in the market and add to your position as they do ?
If the answer is "NO" as probably I suppose, my suggestion is ........ don't try to "MAKE" the market to make profit (which is not so easy as most traders know), but try to follow the market from a position possibly very very close to the market trend.
Don't try to stay in front of the market but try to stay very close after it.
If you look for a very good software to accomplish this second behaviour, Multicharts is a very good one that match your criteria and can help you in your trading, specially if you are able to program your indicators and logics.
For the custom instruments that you create with excel, make a deep search in this forum and you will find that is possible to create custom instruments and custom programming for all you need, even without passing by excel. As usually I use to say, the limit with multicharts is your fantasy because if you want and you can think of it, it's very probably that Multicharts can do it in a way that you can't imagine now.
Think different because the reality is there under your eyes, but you can't see it now because of we all usually think in a standard way using what is already done.
Try to create YOUR new way that will free you from standard schemes
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