Many schools of thought on wedge flexes. I worked for Dave Pelz for while and he always prescribed slightly more flexible in the wedges. The reason was you usually don’t swing them as hard or at full throttle, so you shouldn’t need them as stiff, and the fact you want more feel in the scoring clubs. I tend to agree with Dave. Some want stiffer, but I never understood why other than to try to keep the trajectory down. Others advocate for the same flexes in the wedges. Generally, since most wedges head weights are slightly heavier than the normal progression of head weights in the set, if you go with the same flex, they will play slightly softer. So, since your going to a Senior flex, I would stay with the same Senior flex in the wedges.