For me i think there will be another Mass Effect,they will find a way to resurrect Shepherd or at least some new form of Mass Effect,only time will tell,i really hope the studio doe's make a new Mass Effect.
There is interest among Bioware about this..... but
They are focussing on 3 seperate titles right now, with a possible Baldurs Gate 3 making an appearance within 2 years time.
Must admit Baldurs gate is a classic RPG and for me an updated Baldurs Gate would be a Huge welcome in the gaming world,also the M.E. trilogy is a HUGE money spinner you don't mend something when its not broken,to get rid of this M.E. i think would be stupid of the studio.