One thing that absolutely needs to be done for e-cigs is to address their piss-poor design.
The way the tanks screw into the batteries is crap in that it invariably leads to you inadvertently disassembling the whole tank and dumping juice everywhere when the battery/tank interface threads are over-tightened. And it's very easy to accidentally over-tighten them just through normal use with no purposeful effort.
Similarly, the way the tanks are designed isn't very good either. They do allow you to take them completely apart for easier cleaning, but that same aspect causes the problem above and also makes them prone to flooding (where juice comes out the mouthpiece instead of vapor). Plus just unscrewing them to refill is often times a chore and you wind up having to have a solid surface to put parts on while you are refilling - the chore can't be done one handed and only two-handed if you're really good at it.
Basically, I want a tank that opens with some sort of latch or button that can't come undone accidentally. Similarly, I want a tank/battery interface that doesn't involve threads and screwing-in. I ask for the moon but I digress. One day, when I have the time, I'll design something with NX or CATIA and get it kickstarted. One day...
Also is it just me or are most shops starting to cater more and more to drippers? Drippers are the kinds of e-cigs that you have to manually add a couple of drops of e-juice to with almost every puff and they create massive clouds of vapors. I get that the way those things are customizable probably means more profit for shop owners because they can sell more kit. But I don't like feeling the shops aren't really interested in my business. I don't know, maybe it's just me but the stock of non-dripper tanks, batteries and juices at places seems to be declining as more and more shop inventory goes to drippers.
I actually would love a dripper because they hit soooo good but I can't carry around a bottle with me and drip it on cotton every time I puff. It's just not practical.
On the above conversation about the health benefits of e-cigs - there just isn't enough reliable data to make meaningful conclusions. People should be weary of anyone who says e-cigs are healthy; it's probably fair to say they are healthier than cigarettes, but I'd never go as far as to say they are healthy themselves. And while nicotine does has some helpful side effects (it's a potent anti-depressant; which is why a lot of people with mental health problems are smokers - they self medicate); they don't outweigh the risks of the substance.