DislikedMetastock isn't free. MT4 is an anamoly in the client/broker software world; both an effect of, and a cause of, the ease of entry into the forex market making world (if you don't have to spend a million bucks to build client interface, your IT can go to your internal accounting and position management software; MetaTrader was an absolutely brilliant business model).
There are nowhere near as many futures brokers. You can look at optionsXpress; I have an account, but am not otherwise a stakeholder. In general, look at ones who own seats....Ignored