Baron and elder dragon should kinda switch roles in my opinion. Baron spawns at 20 min is too early in the game and should be backed up 5 minutes or make it a tiny buff the first time, larger the 2nd time and so on. Example: 1st buff it enhances minions only to help seige; 2nd buff you get AD/AP and first buff (same as it is now); 3rd buff is the 2nd buff plus an additional 10-30%
So baron would count for teams different, if red team got 2 barons and were going for their 3rd but blue team never got one then they would get the lvl 1 buff only.
Then you have elder who spawns at 35 minutes, enhances the prior dragons you have taken and is weaker than baron the first time you get it, it doesn't make sense. Then the 2nd time you take elder its boost is insane but when have you ever gone for 2 elders? Elder buff the first time should be equivalent to baron buff now.
If I could change everything I would make baron a strictly minion buff and then boost minions only and elder dragon would be for champions to give a bit of diversity on your choice going do I boost the minions or myself? I would make baron minions only because rift herald doesnt do anything to champions to keep the same theme on the top side of the map where bot side is about boosting champions.