I am conservative in suggesting build changes because I cannot know what is important to the person, but I will toss out that as goes my StJ/Inv Brute, I took Sweeping Cross and added Cross Punch for 1-2, deja vu action.
I tweaked what you had, dropping Initial Strike for Sweeping Cross and dancing some slots/enhancements around. The comparison to what you had can be summed up as:
I know you said you already said you had an Energy Melee scrapper but StJ...let's talk about StJ....
As noted above, I made an StJ/Inv Brute. I have him at 50 and largely slotted out. He's not bad. He doesn't really compare in terms of delivering a beatdown to my SS/Bio Brute...and that's annoying as all get out. Yeah, StJ does not have Rage, but it also does not have Rage crash and you do get the combo mechanic for dealing out extra damage. That does not put it in the same ballpark as SS. Think of it as more lacrosse instead of baseball. Let me -=STRONGLY=- suggest you try the finished product out on the test server to see if it is giving you the umph you really expect.
I may finish up my StJ/Inv Brute if for no other reason than he has an awesome costume, though it has to be easier to make a new character and give him the costume.