I was in a similar situation last year. Trying to avoid the GMAT, I applied for a Bachelor in Management at LSE and got accepted. I started it, not very convinced this was the best option and it turned out it was not! I quitted, started working and then I took the GMAT (although my score was not very good, 650) and applied to LBS, LSE, HEC, EMLyon, ESCP, SSE and RSM and I got accepted in my first option, LBS!
So it was worth taking the risk!
Personally, I would not go to Grenoble, hence I did not apply there. The school is good, but I do not like the fact that it is not in a big city, but you might not mind about this. So it's really up to you. I would gain some WE, read the GMAT and apply to more schools
a 1 WE is always good and you would have a larger range of school to choose!