Mercedes has made a total mess with naming. Before the were "letter" Class, CL(K), SL(K) and ML. Instead of calling the small SUV MLK they called it GLK because of the GL. Then they called the 4 door E-coupé CLS, what to say the truth causes confusion if to take the CLA as basis. To restructure the nomenclature some namings might die, like ML, SLK and change status as CLS for instance. And who knows how it could affect the product. What if CLS will be called CLE and S Class 4 door coupé CLS? Will clients avoid the CLS because they think will be seen as previous CLS from a status perspective?
My proposal to naming and portfolio this time (as times have changed) would be:
F Class = 3/5 door city car (like Audi A1, Mini and BMW "0" Series) (F for "Flitzer", sounds like F*** Class? Maybe then the letters M(Mini/Mirco) or K(Klein))
G Class = (famous Geländewagen, don't know if they stop production one day, if yes, see "GLS")
A Class = 5/(3 if ever) doors compact hatch
B Class = 5 door compact van
C Class = sedan, sedan long (if China needs wagon, Coupé, Cabrio (between 2 Series and 4 Series, closer to later)
D Class = 5 door wagon (BMW GT style, yeah I hate it, but that is what people want. At least the name is there).
E Class = sedan, sedan long, wagon, Coupé, Cabrio (between 4 Series and 6 Series, time to have a true 6 Series rival)
R Class = 5 door sports van (well like current one, I really like this idea, it is in fact a sort of 5 GT rival)
S Class = sedan, sedan long, sedan xtra long, Coupé, Cabrio
CLA = four door "coupé"
CLC = four door "coupé" (if Merc wants to join the 4er GC, at least the they have the name, and current CLC will die)
CLE = four door "coupé", shooting-brake, (changes name, not sure if it will affect sales)
CLS = four door "coupé" (should then be the 4 door S-Coupé, hopefully "old" badge will not affect sales)
GLA = compact SUV
GLC = mid-SUV (really stupid they called the the other one GLK, just because of nomore existing CLK and the SLK)
GLE = SUV (will it be acceptable to change from ML to GLE after the third generation?)
GLS = luxury SUV (will have to find the right balance between luxury and utility)
MLA (rival of X2 if needed) (not sure if the namings sound dumb, but for sake of consitency...)
MLC (rival of X4 if needed)
MLE (rival of X6)
MLS (rival of X8) (the name if there, just wait for the market)
SLA = Roadster (soft top?), Coupé (who knows, maybe there will be a market for this, at least the name is there)
SLC = Roadster (hardtop) (new name, will be hard to digest after three generations, but for the sake of consitencey again)
SLE = (name is there, car is not, just forget)
SLS = Roadster (SLS will stop production, new SL gets new name. Acceptable after so many generations?)
SLR = Coupé (the rumored 911 / Turbo fighter, gotta bring back the old badge, "r" stand good for such a model)
And there we are I think. Problems are ML, SL, SLK and SLS. Well it could be kept like "x"LA, "x"LK and "x"L, but who knows what will Mercedes need in future. The more models, the more hard it will be to restructure in future.