With an avalanche of new models on the way, the viability of current niche models is being investigated by BMW.Insiders have told Automotive News BMW is conducting a review of its lineup as the automaker continues to add new models based on the electric-only Neue Klasse platform.Its roll out means that some models, such as the combustion X3 and electric iX3, now ride on different platforms, have distinct styling, layouts and interiors, which all adds complexity to the company's manufacturing process.This has resulted in low-volume models coming under close scrutiny, with the XM, i4 and 8 Series most in danger.?…