looks like they gave you some good advice while I was gone.
Yes, the derringer is a good first dripper, and it's one that is designed for flavor. It can be configured for both one and two coil setups, and it's tiny.
Man, times have changed since I first began to build my own coils. They now have coiling jigs, and tools to make things easier, post holes for the wire to go in easier, and the fact that everything is cheaper all together. For a first time rebuilder, things are in a whole different level.
First of all, you already have a regulated device. I definitely wouldn't go mechanical. your device should handle a pretty low build... .5 ohms. Personally, I would stick with a 1.2 to 1.5 ohm coil, and like others suggested,kanthal 28 gauge. That's been my main wire gauge for a while. (I'm not a big sub-ohmer). 28 gauge seems to bee the go to for 1.2 to 1.5 ohms. I have 32 gauge, but I use that for rebuilding tiny coils.
I would link several videos on how to rebuild, but there are so many to choose from and everyone has their own method. just do a search for "RBA rebuild and you will see several types of rebuilding styles... most of them tend to focus on sub ohming. But the main difference between a subohm build and a 1.2 ohm build, is thickness and size of the coils.. everything else is pretty much the same.
General idea of dripping... forget the tank, and just put the e-juice straight on the cotton. It will require you to keep the juice on hand, and constant dripping, (don't drip and drive), but the flavor is better overall, since you're controlling how saturated your cotton is. Speaking of cotton, I would use Ko-jen-do or Muji cotton. Those are brands of cotton from Japan originally designed for the cosmetic market. It's cotton that they do not put through a bleaching method and and clean it thoroughly. Cotton bought off the shelves usually have been bleached or processed with chemicals. You CAN do organic cotton, but most who do that usually boil it first to get rid of any excess chemicals. Personally, I say just buy the Japanese cotton... you spend about $2 more, but it's worth it in labor and peace of mind.
I too own a Derringer, but I own a copy (clone). I chose a clone because 1, it's much cheaper and 2, it takes regular phillips head screws. I hate having to look for allen keys when I need to rebuild. they do offer a nice handle to tighten down the screws, but I still prefer the regular screwdriver. If you can find one locally, then I suggest go there and ask questions. Watching videos is one thing, but you can't ask videos questions.
I ordered mine online and
this is what I bought. Took me a month to get it, but it works great.
When you get one, let me know. I don't check the forums every day, but usually several times per week. There's a bunch of great people on here, so they to will steer you straight!
happy vaping!