I'm surprised you even notice the difference between brands to that extent! Even looking at those pictures they all look pretty much the same. If anything, the Red shifter looks like it has a higher cut in that area you are talking about, but to me that's a good thing because it would allow you to get a better grip when on the hoods. Any handgun shooters out there? If so, you probably know the advantages of having an undercut/highcut trigger guard. Bike hoods seem no different in my eyes.

I recently went from Shimano 105 to Sram Rival, and I have no regrets whatsoever. Sram hoods feel better in my hands and I don't notice anything similar to what you are describing. More importantly, Sram shifting feels faster and more accurate/secure. Overall, I think Rival is simply a better performer.

That being said, I can go either way when it comes to how the shifters operate. Sram's double-tap does a great job, but as simple as it sounds it takes some skill to operate accurately. It's not hard to mis-shift if you are lazy and don't follow through on your downshifts to larger cogs. Shimano's separated up/down shifting levers makes it kind of idiot proof. Then again, the OP isn't the first one I've heard say the new Shimano ergos cause simultaneous lever mis-shifts. I didn't experience this with last year's 105 group, but haven't tried the new Ultegra so I wouldn't know about that.

I have zero experience with Campy, and other than a little curiosity, I have no real desire to give it a try because I've already standardized on Shimano/Sram compatible drive train components.

None of the mechanical groups are perfect. I think Red gets the closest to perfect, but di2 kind of trumps them all. I'll be looking forward to the day the entire di2 group costs no more than $2k. Until then, I'll be riding any combo of Sram components.