When I was using clearomizer tanks they used disposable pieces that had a premade mini coil inside with silica wick. I ran into the same issue. Mixing similar flavor profiles muted the taste a little but was ok. Mixing and matching with many flavors didn't work out so well. Cleaning them was a royal pain in the ass, best to get several clearo tanks and use one for each flavor then replace the coil when needed. When changing the coil/wick flavor can be changed.
I tried the blotting method with paper towels, it helped but they remained tainted. Always got a hint of the previous flavor. I tried rinsing with water but that wasn't good either. Even when they seemed dry after blotting and giving them several days to air dry it always tasted watered down like adding some water to a soda or something.
I even got some of the silica wick to try and rewick those tiny coils, omg what a pia. IF I got lucky it took me around 10-15min and that's wrapping the end of the silica tight with plumbers tape, fiddling it through ever so carefully. Most of the time the tiny 40ga wire or whatever nutso tiny gauge they used would break or short and after all that time find out the coil was dead.
Definitely stay away from the rubbing alcohol, not only is it likely toxic it likes to crack the hell out of the plastic/acrylics they use to make clearo tanks and drip tips. Found that out the hard way.
I've been much much happier since I went to rebuildables. A bag of organic cotton make up pads was like $8 and has lasted me the past 6mo or so without even putting a dent in the bag. It will probably last years at this rate. Wire is cheap, I got a 5m or 10m spool for a few dollars and haven't used it all up yet. Even twisting it (uses double the wire and the length is reduced a good 30% when twisting). A twisted coil lasts me a couple weeks usually with a brief rinsing and dry firing/pulsing when I change wicks out. Sooooo much easier and cheaper. I think a 5 pack of the premade coil heads with wicks ran me something like $10-12. They would have lasted me a month or so. For the same price in wire and cotton I've gone 6mo and still going. Not to mention I don't run into the issue of 'oh crap, that was my last coil and I have to order more'. Replacing a diy coil/wick takes all of 5min.
So far I've been using a single rta, I don't have others in my rotation or different tanks for different flavors. Pretty much a beginners or worst case scenario. It's still less hassle and easier and cheaper to switch out flavors, wash the rta out, rewick etc than it was when I had 7-8 clearo's at $7 a piece. For what I spent in clearo tanks alone it paid for a dual 18650 mod with a decent rta. The funny thing is I avoided going big with rta's and mods with separate batteries because spinner style ego battery mods and clearo tanks were 'easier'. HA. It's been the complete opposite experience for me.
Technically if you have a large slush fund or disposable bank account, the clearo's can be easier. Especially if you have $50 worth of tanks laying around and $40 worth of premade coils so when changing flavors or one breaks or burns out you can just toss it and grab a new one. Convenience comes with a price though. Obviously if you get a flat tire on a car, changing it out is more work than just signing a new lease but not without a hefty premium.