If you have adopted an all-in-one strategy, there is a good chance the functional perimeter of your single software does not cover all your needs: it may be very good at managing orders, acceptable at dealing with portfolio management, and poor at handling compliance.
How far may an all-in-one software be from what makes your business unique?
In any case, you should be aware of this: there will be a functional gap.
The question is: how are you going to address it?