I am worried about some runes

So I was looking at the runes and honestly, I fear that some of the rune options at the moment are never going to be balanced. This is either to them being too weak (for good reason) or having the potential to be stupidly strong.

I'll use the Legendary: Bloodline and Scorch runes as my prime examples here.

First Legendary: Bloodline; This rune gives the user 1% life with each stack of Legendary. This means at 5 stacks this rune gives the user 5% lifesteal. That is pretty solid but that means you need at least 150 CS at the bare minimum to get the full effect of this rune. Now there is a good reason for this being so weak. Lifesteal is an amazing stat and if this rune gave the user say, 10% this thing would honestly replace every single Lifesteal item because you are still going to be healing just AOK. That along with the other healing options and I can easily see why this rune is so weak.

Scorch is in a similar spot only giving about 10-50 magic damage on-hit every 4 seconds. This is actually a really strong mastery that could be the cause for winning a lot of trades and as such it is kept a little weak so people aren't taking it as a much have. Even right now it is fairly strong but if it were any stronger then I feel like this could be a must have for every single champion that could use it.

That's why I am worried about some of these runes. They just feel like they will be either too weak compared to the other options in that line but if they were to be buffed they could completely break and wrap the game around them. For proof of something like this just look at how 25 heal pre-auto caused Ardent Censor to become one of the most busted support items in the bot lane. That is what I am worried about some of the runes I have seen thus far. They just have the kind of power that leads to being nearly unbalance-able.