I am sorry but Tesla is already offering that
So what?
I'm sticking to my forecast: when big carmakers (BMW incl) will start offering loads of EVs in the next years, Tesla will be somehow toasted! Unless Tesla finds out some revolutionary production technique how to produce mass-volume cars faster, cheaper & better than anybody else. Since even before Tesla S Mk2 hits the roads, others will be ready with much much better products.
Tesla's advantage is they are a trailblazer ... They spend other people's money to be the first in the market ... generating losses and even negative net cash flow!!!! Even 14 years after.
Battery tech is getting cheaper; established carmakers are readying modular architectures for EVs; and that's it: they already have production facilities built & ready; supplier chain established; sales & afters sales network established ... many of them globally!
Not to mention high level of customization most established car makers are offering. Eg. Tesla will offer moderate customization for Model 3 - to make the production quick, simple & cheap as possible.
Tesla - right now - is still a carmaker that produces 80k cars a year. While they plan to produce 500k vehicles in 2018. Really? Do they have all the logistics set up? All the sales & after sales processes too?
Growing form production of 80k cars to 500k cars in a year is just nuts! At such expansion rate quality control (of products & even services) goes to toilet!
Sure, right now they still have enough advantage to make some moderate mistakes, but they can hurt brand image badly! Also since they are entering premium end of mass-market ... Model 3 is much more every day product than Model S and Model X which have attracted tech-savvy early adopters mostly.
Data shows many Model 3 prospects come from Economy brands like Toyota, Ford, Nissan, Honda, VW, Hyundai etc. While Tesla S & X customers mostly migrated to Tesla from premium brands.
Like Bob Lutz have said: Elon is delusional if he really thinks he's the only one getting the car business "right" while others have done all wrong since the birth of the car.
The point is established carmakers operate on different business model than Tesla (which still operates like start-up - burning other people's money & generating loses & negative net cash flow) ... migrating to EVs slower & @ different pace ... since they have an established market & customers to cater, and mid-term business plan (incl all the financing) in motion.
But the EV market is waking up ... the tech is booming ... prices are falling. And when others start to roll out Evs, there will be plenty of them in the market. And Tesla's offer will be lost in the ocean of EVs. They'll have to FIGHT for customers. With better & cheaper products. And that's not easy. Not at all.
Tesla needs a wealthy parent. An IT company. They will somehow have to invest all the piled up hundreds of billions somewhere. Eg. Apple sits on $250 billion (!!!!) cash reserve! Elon would be wise selling Tesla in the next years, and starting focusing on Hyperloop & SpaceX.