Econ,
Sounds like you are going through the same hoops and concerns that I did a few years ago when I was looking to save commissions over IB s. I think that as Bootsy says if you haven't got a 100k ac where TT s $800 ish a month is a small percentage, then there is no one broker that fits all. The Ironbeam issue you found is the main reason I am still with Dorman despite the patchy poor CS.
The one thing for me that is a must is Sierra Chart, back 10 years ago it had the reputation of being cheap and cheerful and I paid the extra for esignal. 4 years ago as a result of a post on here I took another look, and was amazed the progress was superb but it's still cheap!! If you trade off charts then the chart trade function is excellent.
Thanks for your recommendation! More research is telling me that there is no difference for futures brokers. For eg, dorman & optimus both state that your account funds r held as “Customer Segregated”. This segregated account structure protects you from suffering a loss, should your broker or clearing firm file for bankruptcy." "but there is no level of regulation or other safeguards that can 100% protect an investor in the case of fraud or other inappropriate activity."
Of course this just means that you should diversify with 2 or more brokers. International clients of MF Global took 2+ years to get their funds back.
https://www.dormantrading.com/about-us/safety-of-funds/
http://support.optimusfutures.com/customer/portal/articles/757975-is-my-money-safe-
TT's $800/$100,000 is close to 1%. That's pretty ex if you ask me. I found some brokers offering the TT platform at reduced costs. Optimus seems to offer this. Have not demo-ed though.