I found myself very productive with just 2 machines, one drum machine/sampler and one synth, or 2 synths.
When I work with more than 2 machines I found myself less productive.
I also think that computers, iPad, tons of plug-ins/software can be a limit to productivity.
You will be end up using each item at 5%/10% of its capability because you will not know each machine very well.
Less is more.
The best electronic music has been made with minimal equipment.