The biggest thing that jumps out at me about your description is “13 people”. If that’s the total # of employees (Accounting, Engineering, Service, & Manufacturing), then I guess a lot of your folks wear many hats.
When we started with Epicor we had about 30 people, but only about 6-7 regular users (people that open the program every day (an accountant, AP, AR, a sales entry person, a buyer, & Mfg manager/shipper), and and only had 8 user licenses. We found that the Epicor system was way more powerful than we needed.
We opted not to use many of the features and functionality. Not because they didn’t fit our business processes - but because we didn’t have anyone that really understood the system as a whole - and more precisely didn’t have the manpower to do the setup and maintenance required for some
of the modules. I’m telling you this the system is usually shown off in a way that can be overwhelming. Yes the manufacturing modules have the ability to assign resources (people, equipment, etc…) for optimal scheduling. But you can also run it with out doing any scheduling, or even tracking labor.
With only 13 people, I hope one is a full time IT person, and not just one of your engineers that is SAD (System Admin by Default 
). Having someone to invest time in learning the system, and using it properly, will go a long way in using E10. As for customizability, E10 knocks it out of the park. And for support … well, you’ve already found this place.
Also, read the following. It’ll give you some insight about some pushback you’ll get when “your” new system doesn’t work the exact way “they” expect it. And some pointers to make a new implementation go smoother.