Trying to answer as best I can: Your culture won't smell like alcohol and it won't smell like bread yeast. It will have it's own unique sourdough smell.
Yeast gives off alcohol as part of the process. Different yeasts have different tolerances for how much alcohol they can stand. Basically once the alcohol gets to a certain concentration, the yeast will go dormant. Similar mechanics with beer.
The fact that your cultures doubled is good news. But remember, once the yeast exhausts the available sugars in the flour, they will stop bubbling. That's normal.
If you are leaving your cultures out at room temp, you'll exhaust those sugars quickly.
When I refresh my culture, I leave it out on the counter until it's bubbling and has almost overflowed the container. At that point it goes into the fridge. I will leave it there up to a month before doing another refresh.
Hard to explain but your culture should have a sourdough smell. I can't think of anything to compare it to. Using supermarket sourdough for this may be an exercise in futility as those breads can be pretty lame. My guess is there's nothing wrong with yours.
The only thing I can think that's different from what I do is leaving it out at room temp for more than half a day.
You can abuse sourdough starter up to a point but once you say you're sorry it's your friend again.
Time to make some bread?!
Nothing that happens in a starter in the first few days is normal, in the sense that it doesn't behave like a mature starter. During this time, the bacterial flora in the starter is in constant flux, and you need to wait until the desired bacteria have prevailed, which will take some time.
It is not impossible to do something wrong, but you will only know it when the starter has stabilized, or rather failed to. Until then, just keep the regime exactly as prescribed, no matter what visible changes happen.
Best Answer
Rye is fine for sourdough. It's actually the main motivator for sourdough since rye's rather sticky doughs take considerably worse to yeast as leavening than wheat doughs do. But while using sourdough is more relevant for raising rye, cultivating it works similarly well with wheat.