Does Deathfire touch need some love?

In it's current state it's only seems a worthwhile pick on a handful of champions who synergise extremely well with it. All keystones have a nice powercurve and feel useful from level 1 thil 18. DFT on the other hand isn't noticeable at all in the early game and wont even finish off a target at 4hp because their health regen is more potent than the burn.

For a lot of champions it simply takes too much time for it to be useful, and isn't worth the time you spend essentially not having a keystone. Considering most mages can realistically only choose between DFT and TLD they end up being forced into the latter, not because they really want to but because it's the only option. DFT might eventually outscale TLD, but the extra poke and kill pressure TLD adds the entire game is often times a lot more useful, especially if it ends up helping you win trades and secure kills.

Would it be possible to make the base dmg scale per level(like TLD) with reduced scaling from AP / AD? It's fine that the keystone is less useful early and more lategame oriented but i feel the curve could be slightly smoother than it is now as it severely limits keystone options.