If you don't mind a little bit larger of a device you really can't go wrong with either the Innokin SVD or Vamo. I bought both recently and they are wonderful devices. Don't be scared of the term mod or VV/VW devices. Easy to use, very adjustable, and also economical. Most don't want to drop $160 on a Provari. Yes they are quality but with all the expenses incurred with just starting off it sometimes make sense to be conservative to begin with.
Either a SVD or Vamo will run about $40. Add 1-3 rechargeable batteries and a charger and you can get a complete kit for $60-$80...well you need a tank or carto as well. Both devices will run as variable voltage or variable wattage. I personally prefer wattage as I can switch different tanks without worrying about formulas or charts. Drop a tank or cart on there, fill with juice, start at a low wattage and slowly increase until you get the flavor, throat hit, and vapor you want. If it tastes burnt, back the power down 1-2 clicks and keep vaping. So easy.
The menus on both systems will tell you the resistance of juice delivery device (nice to have but not necessary), what your battery charge is, what power you are running at (watts or volts), and just by clicking one button (one time) you can easily adjust the power. Also both devices allow for 3 different battery configurations using pretty standard 18350 and 18650 batteries. With a single 18650 and even being a pretty heavy user you can get around a full day of usage before recharging.
I prefer the SVD but either are great. Add a clearomizer, a Protank (very good and easy), or a cartotank and you are good to go.