Wow, just found this thread after seeing a picture in the MMpro one; absolutely stunning workmanship!
On the issue of it still being a mini erevo or not, it is. A custom chassis is no different than an aftermarket one bought online or in a shop- its just a homemade one that could easily be repeated and sold en mass if people really wanted it (cnc'd the main upper and lower plates I believe?). The point being really that it is the spirit of the machine that determines what it is- tranny & axles/ suspension design being the main factors.
For example, when you look at 99% aftermarket emaxxes, with UE this and Gorillamax that, you still call it a 'Maxx' dont you? Its just got alot of upgrades that replace the stock parts for something stronger, longer or better designed for the purpose you have in mind.