If you have the time and determination you can implement ANYTHING via custom packages (The IDE doesn't really matter, it just makes creating the packages easier .. or harder).
You can still use two Workflows in SPD, you make them trigger on different items, that have the first workflow modify a list item (or create a custom column for this), and the 2nd Workflow will fire on this modification.
Additionally, you can create custom activities that you can utilize via SPD. Paul Kotlyar has a project on CodePlex with Custom SPD workflow activities, which includes starting another workflow.
You do have some thresh holds to be aware of when using SPD Workflows:
It would still be wise to do a comparative analysis on SPD Workflows, and other ways to implement your logic (event receivers, timer jobs, etc) and be sure you are using the best tool for the job.