I am interested as well. Do you onboard international investors? And what about ring fenced segregated accounts for larger investors?
Someone had sent me an email from AusPrime you should check them out. They even send me a demo: link: https://portal.primexm.com/Home/Login Username: sb@ausprime.eu Password: Ausprime1!
Little late to this one but if you want low rates per volume while still being able to talk to someone when needed: https://www.cannontrading.com/services/match-beat-rates
I trade similar size and have been using Amp but am not entirely happy. Any communication to discuss with them has been difficult to progress. When I was trading prop, we had Goldman Sachs as a broker and were on $0.50 per side. God knows what the firm were getting before they slapped on their profits. Looking for a change also. I need Sierra Charts integration for chart and execution though, so thats why I'm still with Amp. IB are seriously expensive in my mind and margins are massive, then add in when they increase over high volatility events its massive. I think it was as high as $17k to $20k margin per CL contract around May 2020.
Take a look at Sierrafutures, a division from Stage 5. Lower e-mini commissions compared to AMP as well. Or you can go directly with Advantage (Sierrafutures uses Advantage Futures to clear with). However i haven't explored that myself just yet so i don't know what kind of customer service or commission rates you can get at Advantage.