Hi Seliah,
articy:draft is mostly bound to CPU speed and RAM and the GPU to some degree. Depending on the Size of your project, more RAM is always welcome, but 4gb should be enough for a lot of reasonable sized projects. For example my Workmachine has "only" 6gb.
Now the more important factor is CPU, the more the better. It usually is a matter of budget and personal taste, what some consider a perfectly workable speed is for some others incredible slow. I had articy running reasonable on a Surface Pro (which is a bit slower than the Core i3-4010U), considering its size and hardware. Again, my Workmachine is a Core i5 at 2,8ghz. And i can work with it quiet well. (Note that development, profiling and debugging usually takes a good chunk of performance out of a system, and its still doing quiet well). I wouldn't worry to much about harddrive for articy, except for loading and saving a project we rarely access the HDD.
One thing to note is that the GPU shouldn't be too bad, because of the fact that articy uses a hardware accelerated UI interface. Rule of thumb here is, if it runs a DirectX9 Game at a decent rate, it is enough for the UI. The Intel HD 4400 is ok'ish but, again depending on taste and budget, could be better with a dedicated GPU.
In conclusion, all these systems can run articy:draft at different speed obviously. It heavly depends on the project size and how much one is willing to sacrifice for mobility and willing to spend. But i wouldn't worry to much about articy; take all your desired work scenarios into account (Visual Studio, Unity, Photoshop etc.) and focus your descision on these. If its good for them, its good for articy.
I hope i could give you at least some help, its always difficult to choose hardware.
Best regards
Nico