Didn't read it all, but the burnt rubber taste is almost always caused by a melting rubber insulator on the bottom of those clearo coil heads. This is why a lot of companies have went to silicone insulators.
When I first started vaping with some random Chinese CE4 style clearo, I also experienced this and it was awful. Took me a while but I figured out what it was. Once that flavor is there, it's like a skunk and hard to get rid of.
Honestly, in 2015 there is zero reason to use those cheap ego-style clearos anymore. Some of them are OK like the EVOD, Protank, and a few others, but I must ask "why?" Why bother with them when there are much higher quality tanks out there now? Do yourself a favor and just stop using those cheapo clearos. Go buy yourself a Kanger subtank mini and be happy.
You don't have to rebuild anymore to get a quality vape. If you don't want to sub-ohm, that's fine -- these tanks come with a 1.2 coil. The subtank should be THE tank that every noob walks out of a vape shop with from DAY ONE. There's zero reason for it not to be. A noob can pop the 1.2 coil in and vape it all day and be happy. When he gets ready, he can even rebuild with it with the RBA section.
Thanks BigEgo. To answer your question about "why bother with EVOD and Protank" - mainly because as I explained in my original post, I'm giving one of my iTaste VV's and some of my EVOD / T3S / Protank minis to a friend in need who wants to quit smoking. But also I like to have them around for quick convenient devices to take "on the go" with me in a hurry and/or in situations where it's not convenient to keep stopping to fill my Nautilus minis. I agree with you on point though - I'm much happier with my iStick with Naut mini (and soon to arrive, my Heatvape Defender with Anyvape Peakomizer 2 which I'm sure will be nice) , but it seems a shame to just throw away the other gear when it could come in handy and is also allowing me to give something to my friend to get started with.