I support the cap of 50 simultaneous trades for two main reasons.
#1 If someone has a ton of trades open, they are probably waiting for the bulk of the trades to "turn around". In other words, the trades are loosing, they know it, they aren't doing anything about it because it would mean showing a loss. Some nasty managed account people do this.
#2 If you have a ton of trades open, and the market swings either way then you are probably going to get hurt, really hurt. Probably hurt more than the broker can protect you. Just because you sign the documents and the "Additional Risk Disclosure" doesn't mean you know what you're doing, or that the broker can babysit you.

If someone has a ton of loosing positions open with no stop loss, what happens in a large movement or after enough time? The broker has to do a margin call. This is more than uncomfortable for the broker, it is bad business for the trader and the broker. With all of the 10points3 variants running around, I'd be surprised if the broker didn't need to eat more than the account when the account finally dumped.

I was going to run GridMACD, but it has 30 trades open at once. 30! that is some serious stuff going on, and a lot of margin in use. How much margin does that eat up?!

On to News. I can't think anyone is in their right mind trading News against the broker. They have to fight you or enter the market. If they enter the market, they may not be able to get out. While they *GUARANTEE* execution to you, they actually need to find an *Over The Counter* buyer or seller. Nobody is playing nursemaid to them helping them get rich on 1 super high risk trade per month. When they reduce your risk, it increases their risk. If you want to trade news, go to an ECN. HotspotFX, Currenex, MBTrading, FXAll, take your pick. Don't blame the broker for trying to cover your ass and his at the same time.