Thought I would give my 2 cents. First and foremost, I appreciate your replies to the many threads in the subreddit. It has provide myself (and I imagine many others) insight to why certain design choices are made, whether people agree with them or not. Keep it up!
With regards to rez while ulting, I agree with your sentiment of giving players more choices in the way they play. However I think the issue in this case is that one choice seems to have no risk and will be abused in higher difficulties.
Reading the situation you personally encountered ingame, I can't help but think you would've had no risk if you rezzed your teammate personally instead. (why get someone else to rez and possibly die when you could have told them to back off for 5 seconds and rez him yourself, completely invincible?)
One again, giving players choices is great!! But they all need to have a certain amount of risk associated to them, or else there really isn't a choice now, is there?
So I guess a question I have is : Where is the sacrifice in opting to rez while ulting? Where is the risk?
Here's a way that it could potentially be balanced to have two choices with a certain amount of risk involved:
Instead of being invincible during his ult, every time he dashes his shield instantly replenishes. (Maybe he takes reduced damage in general as well)
This way, if he opts to fight he can still do loads of damage and survive, giving his teammates a chance to rez. BUT if he opts to use his ult to rez, he can't dash and replenish his shield, therefore potentially dying in the process.
I'm sure that my "solution" isn't perfect, but i hope you can appreciate how in this scenario there is risk involved in both choices, making it a tougher, more interesting one to make as a player.
Hope this helps. Looking forward to launch.