SC is not free with AMP any more. take a look at in jigsaw site, they have some offers for black friday. I use SC and purchase jigsaw recently.( Didn't install yet..)
Had mine developed for my own use. But I really like Ninja trader, with the exception limited to 500 symbols and Ninja 8 with is awesome automation and programming. Call Ninjatrader as they have there own brokerage. See if they can match same fees, am unclear if they rent or give Ninja if you are a client. I liked being use the dom and chart, can trade on the chart too. Seldom had problems like with Tradestation.
I use tradestation charts and the DOM of jigsaw as it is stable and full of information. Not free but effective for me.
Late to the party and you may have already chosen it, but I'd +1 Jigsaw Daytradr. Been using it about 1.5 year and love it. I scalp treasuries myself.
Here is my experience with Motive Wave version 6.5 I worked with a few trading software suites and wrote custom indicators is various proprietary formula languages and industry standard languages. Motive Wave is one of the most underdeveloped on I've seen so far. Most of the the crucial features are glitchy and buggy. For example the charts settings don't stick I mean if you enable cross trade instrument and reopen the chart the setting is not saved and the trader may enter trades on wrong instrument. Also when symbol is changed in the chart the orders are entered at wrong prices seems like the the orders are entered at prices of the previous instrument loaded in the chart. The Java SDK is poor and the class methods make little sense. for example the text of a label is entered at the constructor and there is no setText() method for the label instance. if you want stable and mature platform stick with Sierra