What if enchanters were LESS interactive?

Is it possible that the problem with Enchanters is not that they don't get/need to harass champions in lane but rather that their peel and protection abilities are just as good for protecting themselves as their allies? If you jump on Janna's adc, she'll shied, tornado, ult if she has to and you just eat a bunch of damage from the adc while accomplishing nothing. If you jump on Janna herself she still does the exact same thing and Lulu is basically the same way. Shouldn't there be some kind of tactic the enemy can engage in to outplay these mechanics?

What if Janna's shield didn't apply to herself? What if her Tornado started to charge like 200 units in front of her so there was 'dead space' between herself and the minimum distance an enemy needs to be from her to get insta-nado'd? Then Janna would be very vulnerable as a priority target for assassination. She would probably play even farther back in teamfights, but an assassin that pulled off a really good flank would actually be able to kill her and there is such a thing as TOO far back to where she's unable to easily help her team or is herself isolated.