8+ high quality inputs for beamfroming and "...beginner friendly..." are competing requirements.
There will soon be the audioinjector which attaches on Raspberry Pi and would be a relatively pain-free option for what you mention. You can program the Raspberry in a number of different ways including "low-level" C to high level Python or other.
Another option would be to look for a multi-channel USB sound card which is Linux-friendly and attach it, again, to the Raspberry Pi (or small form factor pc). An older iteration of this one was just great for this purpose. And you get low noise amps, phantom power for mics and an internal DSP engine for basic preprocessing (although that was not accessible to the linux driver, at least a few years ago). This option again would give you the ability to program the multi-channel aspect via established hardware and software interfaces. Also, you might want to have a look at Jack and Portaudio.
Hope this helps.