Couldn't agree more with the OP. Natures Touch shouldn't get interrupted in my opinion.
You are not really asking a question but i just thought that maybe i would explain to you why nature's tpuch and energy shield would both be well-overpowered if they were uninterruptable. Well, you see, energy shield is just abundance. You may ask how is this so? Well energy shield consumes more energy than nature's touch, and you ask why as well. The answer is that abundance increases hit-points (hp) right? Well, energy shield basically gives you almost the same amount oh hp as abundance would with the same amount of skill points; but energy shield fills that hp gap with full capacity heal, basically saying that it is abundance and the hp is already healed up that is making that gap.
The developers of the game thought that they would reuse user attributes and implement them into mob formulas, but changing the name of it, such as thunderclap being closely similar to lightning strike. Since you are asking that energy shield be uninterruptible if nature's touch would be, then everyone will find it hard to kill bosses such as bladewing, shivercowl, swamplord/swampking, and more. Actually, if nature's touch be uninterruptible, it would make any druid-like mob that heals itself impossible to kill, deadroot, falgren, and even Aggragoth, since the tamers around it would just heal it (but since they run of energy, this is still possible to kill aggragoth).
Regards, RoyalSeraphim of Taranis