Multi track recording on a Mac Mini into Cubase


I’m thinking of buying a Mac Mini, base model (2.3Ghz i5, 2GB RAM, 500GB HD) - upgrading the RAM to 8GB and getting an external Thunderbolt HD. I want to use it firstly as a multi-track recorder from my Allen & Heath ZED R16, recording all 16 channels simultaneously into Cubase. While recording I will not be running any plugins. Once the tracks are recorded I will want to be able to edit them, fixing mistakes (of which there will be a lot), maybe performing multiple takes for certain sections and comping together something that sounds good. At this stage it is possible I will want to add a few VST’s here and there to add some shine to the mix, and maybe even the odd VSTi to beef out certain sections. Generally though the use of plugins will be very light but there will be a large amount of high quality audio files for it to juggle.

Is anyone doing anything similar with a similar setup?
Would you recommend any changes to the system to avoid any heart ache later on?
Does anyone have any cheap Thunderbolt HD recommendations (at least as cheap as a Thunderbolt device can be at the moment)?