So, basically what's left is a 55-250 STM...maybe even a 70-300? Maybe they'll go crazy and release a nifty 50 with STM, but, honestly, shallow depth of field is what makes STM look bad.
I agree, if they didn't put out their new 24/28/35mm primes with STM, it's not gonna be a large trend across their higher grade lenses. At least, until they put it in the 5d Mark IV