Aside from getting a hardware engineer? 
 
I've hired a couple of Hackers with around 300+ programming and 260+ scenario, and some Producers with 200+ Graphics, so should I just look for stats or is there some effect on them like it's better to always pick a Sound Engineer come beta phase than someone with obviously higher sound than him?

I'm pretty sure it just labels their major stats, but I don't know, I could be wrong.

From what I can tell their job title AND their skills come into play. For example, if you have a writer with a high graphics skill and they end up doing the graphics, they won't do as well as a designer with the same graphics skill. I think making hacker specialize in some field is the best option. Though yes hacker on their own are great.