TOS/TD Ameritrade has a nice front-end for OS X. Their rates aren't the best, about $0.50 higher per contract than interactivebrokers, but the platform is excellent. IB is great if you plan on pushing a lot of quotes; market-making; running a matrix of spreads and combinations. If you're low-freq then TOS/TDA is your best-bet.
With over $200K you can probably negotiate your per contract rate to <$1.25 w/o a ticket fee.
https://www.thinkorswim.com/tos/dis...AB3375E62018D6?webpage=main&layout=homeLayout
is there marketmaking functionality with interactive brokers?
or do you need to use another software?