If I start vaping after I quit smoking outright.. is that just a failure?
You've quit smoking for 3 days. That hardly counts as "quitting outright", IMO. I tried quitting cigs numerous times. I made it for over 3 days several times. I always went back to smoking.
I never tried Chantix. I know it works for some people, but there are also some horror stories.
I always enjoyed smoking. I smoked for 30+ years, and was smoking 3 packs a day. I was pretty convinced that I would never be able to quit. I wanted to quit because of health, and the high cost, and the fact that in todays world, smokers are ostracized and expected to stand in sun or the rain or the cold. I wanted to quit because of the smell. But I still enjoyed smoking - and, of course, I was addicted.
I've been off the cigs for 3 weeks today. I don't ever expect to smoke again. Using an eGo, quitting has been easy for me. There is a learning curve, and some up front costs, but I'm already saving money, and I'll be saving a lot more in the future because I don't need to experiment as much anymore.
I believe that vaping works for 2 reasons. One, it provides the nicotine which smokers are addicted to. That's not the only physical addiction involved, but it's certainly the biggest one.
The other reason vaping works is the issue you are having. The "what do I do with my hands". The sort of psychological "where is my cigarette" thing. By vaping, we get an experience very similar to smoking. Some people actually prefer it. Myself, I'm not to that point. I would *rather* have a cigarette. But I don't *need* a cigarette any more.
I don't get jittery, I don't get grumpy. I don't have trouble concentrating, and I'm not constantly reaching for a cigarette. It never stressed me at all. When I feel any need for a cigarette, I vape. It's *not* like quitting before. Every time I tried to quit before was hell. I hated the world, and the world hated me.
Vaping has been a very easy transition.
When I first bought my eGo, I was told here on the forums not to push it, that I should let it come naturally. Some people start vaping and never want another cigarette. Others need to transition a bit slower. I think part of that is the nicotine level. If you aren't using a high enough nicotine level, then vaping won't get you off the cigarettes.
I bought my ego, and I both smoked and vaped. Overnight, without working at it, my 3 pack a day habit dropped to about 1.5 a day. Within a week, I was smoking a pack a day or less. Within several weeks, I was smoking 10 to 15 cigs a day. And at that point the progression stopped. I would be fine in the morning just vaping, up until I ate lunch. But right after lunch, I'd want a cigarette - vaping didn't do it. I'd actually need several cigs before I felt Ok. And then after dinner, the same thing.
After vaping/smoking for a couple of months, I was still smoking 10 or so a day, mostly after meals. I was using 24 mg nicotine, which is a fairly high level, but that didn't get me off the cigs. Then I ordered some juice in a 30mg level. I continued (and still continue) to use the 24 as my "all day" juice, but after meals, when I feel the need for a cig, I started using the 30mg juice, dripping it into an atomizer.
The day I started using the 30mg juice, I quit smoking. I wasn't really planning to stop that day, it just happened. I didn't *need* the cigs anymore. Vaping had already been working for me for everything except after meals, and using the 30mg juice cured my after-meal cravings. And I quit.
I had half an open pack of cigs when I quit. A week later, I gave that half-pack away. I also had 6 full packs left in the carton - and I still have those. They are right here in the room with me. But I don't need them anymore.
I am still addicted to nicotine, of course. One of my biggest worries is that my battery will die, or I'll run out of juice, or something similar. I know that if I'm unable to vape, I'll end up buying cigs as an alternative. But I can plan for that. I have extra batteries, extra cartomizers, etc. In addition to the juice I like that I use all the time, I have I have juice that I don't really like which I keep around as emergency backup. I have backups of everything at home, enough that I could go for a month without ordering anything. And if I leave the house and won't be able to come back for more than an hour, I usually carry backups with me. (A spare battery, for instance, in case the one I'm using dies unexpectedly. An extra cartomizer and a bottle of juice.)
So I'm still addicted to nicotine, and I know it. But nicotine isn't a carcinogen, and I've taken all of the known carcinogens out of the picture. I've taken the tar and ash out of the picture. I'm on a far healthier path than before.
Over time, I hope to lower my nicotine level, and in the long run, I hope I can stop vaping.
But if I vape the rest of my life, that's still a big win compared to cigarettes.
Should you vape? I think you have to decide that. I think that not vaping and not smoking, don't do either one, is ideal. But "just quit smoking" fails for most people, even when they use chantix, or patches, or nicotine gum or whatever. Vaping works for a lot of people, and it's worked for me, so I'm going to stick with it. Once I've been cig-free for 2 or 3 months, I'll start working at cutting down the nicotine level.
Vaping probably isn't as healthy as just "don't vape and don't smoke". Clean air is bound to be better for us than vaping. But unless you live way out in the country, you probably don't get clean air anyway.

For most people, the only side effects of vaping seem to be things that can be taken care of by drinking plenty of water. A few seem to have issues with PG, or with VG, or with flavoring, but as best I can tell, those are fairly rare cases.
A number of people have posted that they started vaping after years of smoking, and they are now back to doing things they had stopped for years. One guy was training to box. Several have posted about taking up running or bicycling because they now have the lung power to do it again. A number have posted how surprised how happy their doctor was with their results after they switched.
For me, the choice is essentially "vape" or "smoke", and it's an easy choice to make.
If you decide you want to vape, you'll find there is a learning curve. You learn about equipment, and you have to find flavors you like, and the way you inhale to vape is a little different from smoking. (More like smoking a cigar than a cigarette.) But that learning curve gets easier since you know about ECF. The people here are very helpful, and it's like an online "stop smoking" support group.
Good luck with whatever you choose.