Kendra

Don't forget to prime your coils when you're putting your tank together! There's no shortage of youtube vids on how to prime the coils, and it is key! (otherwise you'll burn the coil up)
 
It's also wise to do a few pulls on the tank without hitting the fire button and to let the tank sit a few min once you've got juice in it. You want the juice to wick as well as you can get it to.

https://www.vaportalkstore.com/shop/kanger-aerotank-v2/
Kanger Aerotank V2 from our own Vapor Talk store.   

Don't forget to get replacement coils!

Kendra, you're not quite ready for an RBA, that stands for Rebuildable Atomizer. Before you get to the point of building your own coils, you need to master using the prebuilt ones first. Learn to walk before trying to pilot a jet.   

I currently use 6 subtank minis and 3 subtank nanos, also I use a KPT2, all with different flavors in them. The subtank mini is a good choice for a newbie because of its versatility and the wide range of coils available. My personal choice for a Subtank mini coil is the RBA or the 1.2 ohm horizontal coil. I know lots of newbies that started with a Subtank Mini kit and were completely happy with them.

Subtank mini is an awesome all around Tank I have 2 I use everyday

Tanks will last a long time  unless you drop it and break the glass they usually come with a replacement glass. Your gonna need coils for sure  What tank/tanks you looking at?

If I were you I'd go with the Kanger Aerotank V2. Then, if you order that, I'd go with a 1.8 ohm coil and replacement coils for it.

Sub-ohm is nothing to fear. I started in December and have had nothing but sub-ohm devices.
I started out with the subvod kit, and a kbox mini, which is similar to what you've got and what your looking at. I had the desire for more as well.
Now let me correct myself. Between the subvod and kbox, I bought a fuchai and a triforce tank, that rig showed me what vaping could be, so when I got the kbox mini, I was fairly disappointed. Harder draw, less flavor, where as with the bigger setup and more power, I got far more flavor, could breathe thru the tank more or less which equates to more vapor.
But the kbox has adjustability over the subvod so that was a plus. I could squeeze slightly more flavor out of the kbox because I could run higher wattage.
That being said, it all depends on what you are looking for. After the upgrade you seem to be going with here, if you still want more, don't be scared to go bigger wattage or sub ohm. I'm a flavor chaser, clouds are cool, but I want excellent flavor more than anything.
When the day comes for the next upgrade, I can suggest the joytech cubiod mod, it's easy to use, 2 18650 batteries for plenty of power, and will run anyway you want to, be it temp control, power, or their simplistic smart mode. It will run just about any tank on the market.
As for tanks, I'm in love with the triforce, but there are the herakles (less airflow vs triforce) tfv4 (I fought coil life, 3 days was poor) but there are no shortage of options.

I'm positive it's only nine... okay... pretty sure... 

9 That you know of

Personally, I'd highly recommend the Wismec 40W or the Eleaf iStick 50W because they come with the batteries inside, you don't have to buy separate batteries (plus no worries to get the right ones for safety reasons) and the separate battery charger. You just plug in the micro USB cord to an AC adapter into a wall socket and go.
My favorite that I use all day every day is the iStick 50W with an Aspire Triton 2 for a tank. For someone who is new, I'd suggest the Kanger Aerotank 2 for ease of use and inexpensive replacement coils. 

Kanger subox mini is a nice setup. You dont have to subohm with it but you can if you want You can use 0.5 (subohm)  coils or 1.5 ohm coils and it comes with a RBA if you ever wanna try building your own coils. The subtank mini Is a really good tank nice clouds and real good flavor

+1 on the Kanger Subbox Mini kit.  Contains all you need except  an 18650 battery (and I suggest a Samsung 25R5 or LG HE2).
Aspire has many good kits a well, and you can always mix and match your battery (MOD) and tank combo to suit your own needs or preferences.  I would suggest the Subtank mini or AeroTank V2 from Kanger, and from Aspire, the TritonV2 (not the same as what you have), Triton Mini, or Nautilus for tanks.  As for battery (MOD), I would suggest a reliable box-mod like the Kanger 50W (that comes with the subbox kit), Wismec 40W or Eleaf iStick 50W.  The latter two have built-in batteries and won't require separate purchases of 18650 cells.