I highly doubt the old Team Builder will come back.
Advantages of the Old Team Builder:
- You would be guaranteed a role
- You would be guaranteed a champion
- You could potentially get a group of people OK with odd strategies (2 ADC bot, 2 Jungle, etc) (Not sure if this is more or less likely than getting it in Blind Pick)
Disadvantages of the Old Team Builder:
- You were locked into a champion (You couldn't change your ADC choice to better go Duo ADC). This couldn't change because suddenly you'd have people not OK with your pick and want to dodge.
- You couldn't invite players after the queue started, forcing you to lose all your random pickups to play with a friend that just signed on. This couldn't change because it would "force" the new player into one of a few roles.
- The queue time took forever (continuation of the last point, plus people "dodging" endlessly)
- There was no Random option
- Specifying what you wanted for a role ("Support/Bot") would lock you out of other players you'd be fine playing with ("Tank/Bot" or "Mage/Bot")
- No counterpicking
- No bans
- Extremely frequent mirror matchups
You have to put a lot of value on guaranteeing a single role and a single champion to ever make the cons of the Old Team Builder.
Honestly, I'd prefer to see Draft Pick get "Fill" to work like it does in Blind Pick, where it is far more random (only ~35-40% Support in my findings)