I guess maybe you’re looking for something that uses mostly standard bicycle parts. By the nature of folds and small wheels, most bikes (if not all to some degree) need some specialist parts. There are also compromises to be made… weight, robustness, durability. By “rim wrecking” brakes I suspect you are referring to rim brakes (callipers, V-brakes, cantilevers)… for most folders I think they are a good compromise between utility, simplicity and braking power. Hub brakes are great (I have a trike with some SA drums), are incredibly durable, but are heavy; disks are lighter and more powerful but more fiddly to set up and more at risk of damage.
We don’t really have mini Velos here in the UK, but Moultons use mostly standard transmission components apart from some specific stuff for the suspension (though it’s much lower maintenance than what you get on MTBs). Moultons are hugely popular in SE Asia and a lot of their sales are there. Before someone tells me off, they’re not folders but do come apart for travelling reasonably quickly - not something you’d want to do at the station every morning though.
In the US you have Bike Friday and their Tikit model seemed a good Brompton alternative though I’m not sure if it’s still in production. The other BF models are not as quick to fold but seem to be well made and BF has a strong record for support.
As you 
