All the advice you are getting so far is very wise. ( JCnewbie, Boomer2506 and Rosa )
No matter which way you go ( I personally would recommend something with a 510 battery connection ) you will be able to try
Cartridges
Cartomizers
Dripping
If you get an eGo or Riva ( you can get the Riva, an eGo knockoff less expensive at Liberty Flights ) you can also try the Tank system ( some folks love it, some hate it )
And a manual battery is indeed the way to go!
The advantage of something with a 510 connection is that your options are wide open to try different things without having to buy different kits.
My sig says eGo-T cause that is what got me off of cigarettes, I am currently vaping the same system but with a type B ( mega ) cylinder LR atomizer ( cheap, like $8 ) and a mega type B cart. ( 10 of them for $6 and they are re-fillable and look to last forever )
An example that with one of those systems, you don’t have to buy another kit to get a very different vaping experience. yesterday I was dripping ( I’m in the trying different things stage ) I have not tried Cartomizers yet... I may someday.
I am keeping my sig as the eGo-T as that is what got me off of cigarettes.
Keep in mind, the bigger the battery, the longer the battery lasts between charges. I started with the 650 mah in my eGo kit, but my wife ( lighter smoker ) uses that now and I am using a 1000mah battery, lasts me a day and a half.
p.s.
Forgot to address your original question.
Atomizers
Tank atomizers are difficult to clean... you can mess around with them, adjust the wic ets... but are not in any way easy to clean. It is possible to take them apart... but it is not a simple procedure and it is easy to mess one up ( I have... twice )
Standard and mega cartridge atomizers are easier to clean
Tanks are a snap ( literally ) to clean
Cartridges look easy enough to clean, I haven’t bothered yet
Cartomizers are meant to be disposable, use, re-fill a few times and toss them away. I honestly don’t know if they could be cleaned.