No problem for the advice, and I will help the best I can! I started out with the Eleaf TC 40 watt, and both Aspire Nautilus's mini and larger tank, have them both still as backups, or when recharging. I liked the flavor from the Nautilus's but I did not like the hard to hit draw, or what they call the MTL (mouth to lung)! So I went to the Aspire Triton 2, a sub ohm tank, very good tank to get a bigger cloud and a DLH (direct lung hit, or DLI Direct lung inhale).
This is when I no longer needed cigarettes (or analogs)! The Nautilus was not working for me, but that is me! With the Nautilus I was using Ejuice in high Nicotene 24mg (or 2.4%) basically the highest or close to the highest! But with the sub ohm it was way too much, burned my throat and lungs. I am now at 3mg nicotene, and a high VG in the juice, 80VG/20PG. It is working for me, but again that is me!
About your Nautilus! 1. Make sure all NEW coils are primed with juice before firing them! 2. those coils will get a burn taste fast if used at high wattage's. 3. cotton taste is present on all NEW coils, for a good 10 hits to a 1/4 tank, depends on the tank/coils? 4. Even the Ccell coils (Ceramic) have a weird taste being NEW and takes a little while to go away. 5. the Nautilus does not like the high VG juice, it does not wick fast enough and can get that dry hit/cotton/burnt taste.
I have not tried the Uwell Crown tank, but have heard very good things about them! The flavor and clouds are supposed to be good. So you got a winner there!
Now about clouds or flavor? Good question? It is up to you! What do you want? What ever it takes you to stay away from the analogs (cigarettes) is the best for you! It is a personal thing I guess! I am older than you, I am enjoying the Flavor, but I know the younger crowd likes to fill a room with a cloud!

I do it here, my friend is still smoking here, does not bother me, it just makes me hate the smell and cigarettes more!

He can not vape like me with out coughing, and I'll fill the house with vapor! Just to show him how easy it is, he's the one with the RX200 and a Smok TFV4? Trying to get him to quit!!!
Now as for my equipment?
Old stuff, don't really use, but good back ups! Eleaf istick TC40, Nautilus and Mini!
What I use now, Cuboid 150w, Triton 2 with Kanthal .9 Ccells (ceramic coils), Mad Hatter V2 RDA, Alliance V2 RDA by Fogwind.
New stuff on the way = Moonshot RDTA By Sigelei( got it today), Aromanizer Supreme RDTA by Steam crave, and a Tsunami RDA by Geek Vape, still waiting on those 2? I am hoping I will not need anymore stuff, well maybe one more mod? and I have not decided yet, get another Cuboid, or a DNA Box mod?
I do not know where you are from, but I know of some good online stores that I trust and they are cheap!
I like my Tanks or RDTA's because it is easier to drive and not have to drip the ejuice. But for flavor or clouds the RDA's are great!! Cheaper yes, plus you can quickly change the cotton and try new flavors without the mix of flavors, or ghosting they call it!
If and when you decide to go to a RDA here is a Great website on how to calculate your coils and ohms and even how to mix your own juice ratio's!
Here it is =
Coil wrapping
Feel Free to Start a conversation (click my ID and use the conversation, it's like a email) if you need any help!