Hi aurora_ray,
I'm actually reaching out to the community for exactly the same thing. However my main tool is C#, I doubt I could get up to speed with C++ or would even want to as execution speed is not the highest priority for me, a couple of milliseconds latency is fine for me
I posted in the Trading Platforms forum if you're interested.
A few tips, SciChart is totally awesome for charting (that is a component you'd need to buy a license for however). That is WPF though, the guys at Modulus FE are selling their StockChartX library for about $1500 USD when I last asked them.
QuickFix is great and free open source. Recommended.
Speaking of design/architecture Akka is looking really good for event based architecture reactive messaging patterns however not sure if there is a C++ port yet as I'm using Akka.NET.
Reactive Extensions probably can't be beaten for the WPF GUI, however again is this even available for C++? You sound like a much more experienced dev than myself. If I could click my fingers and know any language it would indeed be C++ however I've been studying my ass off with C# for years so the sunk costs are too high to change now.
Oh and 'NoSQL' looks to be the way to go for persistence... many hedge funds moving in that direction now. MongoDB looks great and easy to work with.
AlgoTrader looks like a nice package but their price guide for a small operation was 10k a year. Hope they don't mind me quoting that here. Which is why I'm moving in the same direction as yourself.
Cheers!
Chris