^ I thought Scott or Eni said the i5 was going to be some sort of crossover. SUV/Van-ish...
I have this feeling that a sedan shape is too conventional for the i line (in BMW's view)
The whole time the BMW i product strategy consisted of 3 anchors: a megacity car, a halo sports car, and a family car.
i3 is a megacity car, i8 is a halo sports car, while i5/i6 is destined to be a family i car.
Initially a sedan had been considered in the "Project i" strategic product plan. Then a general trend towards crossovers & SAVs forced BMW i product strategists to reconsider the sedan option - in favor of crossover / SAV. But with the Tesla S success a large sedan / 5dr fastback is again on the table, and being seriously considered. Yet BMW marketing guys want to offer more space & higher sitting position - to attract SUV buyers as well, and not he sedan customers only.
There are some ideas to offer a car similar to 5er GT layout: so, a Progressive Activity Sedan (PAS): a 5dr vehicle with a hatch, coupe-like roof line & elevated sitting position.
The problem is that such crossover hatches are not really popular in US, not even in a premium segment. Therefore a crossover-SAV seems a better idea due to its broader appeal - especially if offered in REx or in Plug-in Hybrid version.
Yet Tesla X is coming in some sort "hatch-on-steroids" layout (similar to 5er GT), and BMW product planning decision makers will monitor the sales performance of Tesla X very closely.
In the end the financial & technical aspect will be a key factor here. Meaning: which vehicle is cheaper to develop & which one would generate higher profit margins & perhaps even higher sales volumes.
A large sedan would be more premium & priced higher yet the sales volume would be lower than the crossover / SAV sales with a bit lower price since it would target a broader customer pool.The numbers will decide exactly what car the i5/i6 will be.
Mind that future BMW core vehicles (like X5, 5er, 7er etc etc) will also be available in plug-in hybrid variants. So it makes much more sense the new i vehicle (i5/i6?) is a full EV or EV+REx, and not a plug-in hybrid. So, which kind of layout is more suitable to be EV / EV+REx?
But in any case ... with the next i model BMW will directly rival Tesla: either the Tesla S or the upcoming Tesla X crossover. And that's quite a challenge for BMW: since the cars will probably be in the same price segment too. So, they'll have to make a car that will rival Tesla in performance & economy & usability.
Anyway, i5/i6 is still in a very early product development phase. I guess BMW bosses will lock their eyes on Tesla for a few months, and then they'll decide how to respond. Since Tesla S has impressed BMW Board members & engineers VERY VERY VERY much.
My opinion? Due to non-universal 5er GT appeal a PAS layout for i5/i6 is not very likely. A large sedan has its space & usability limitations. So a SAVish crossover (some sort a mix of a SUV+MPV/wagon) seems the most optimal choice. It will have a broad appeal, it will be practical & spacious. And sportiness is less important in such car's case than in sedan case, so ... I am under impression the i5/i6 will be a crossover somehow similar to Infinity EX in shape.