2 ideas for dragon

Currently, the dragon spawns are randomized throughout the game. My idea is this:

Starting at five minutes, have the same generic dragon in the pit. The buff you get depends on the minute it dies. For example:

5:00-5:59 - Infernal buff 6:00-6:59 - Cloud buff 7:00-7:59 - Ocean Buff 8:00-8:59 - Mountain Buff

This would probably make cloud dragon never chosen, in which case I would say minor buffs would be acceptable. This would allow strategies to kill dragon at a certain time. For example, during mid game skirmishes, if a tryndamere is fed, a mountain dragon at 22 minutes would help him a lot. Likewise, if a fed assassin wants to get picks but is very squishy, a good ocean dragon around the 15 minute mark would help. There are many situations but I feel like this would be an amazing addition to the game.

My second idea would be similar to the Rift Herald and Baron's interaction. At 35:00, a bigger dragon would come by and either devour or shoo away the previous one. that one would be the elder dragon. This is just for cosmetic purposes, but it also put a strict time in which elder will be there, instead of a normal dragon spawning 34 minutes in, and if a team waits to kill it for 5 minutes, elder would appear at 39 minutes instead.

What's your take on it?