For right now I am just using a SMOK TFV4 tank, and sometimes a Vulcan rda. The smok tfv4 runs through juice and the vulcan is too tight of a draw and doesn't fit very big wire. When I do build on it, I use 28g (because that's all I have right now and pretty much all it will fit, would fit 26g too) and I build either single or dual coils. I like to drip a lot and not re drip too often. I build horizontal and vertical coils, usually horizontal. Haven't looked too much into a deck/well-less design, what would be the benefits?
I seriously think you should actually spend your money first to try out a few clones, because once you actually use a few drippers I think you will find yourself leaning one way or the other on the following types of design features/options:
1: side airflow, or bottom airflow
(and there is also a few with top intake, channelled down to side - eg: manta)
2: single coil friendly; most drippers are dual coil friendly
3: convention post arrangement versus innovative post arrangements
(innovative arrangement examples: aris, veritas)
4: ease of inserting coils: eg: magma, manta, velocity
5: chuff cap;
chuff cap makes for convenience compared to pull just the drip tip off, or taking the whole topcap off, which can interfere with your coil/wick or end up spattering liquid about.
6: post holes:
post holes make for ease of inserting coils.
magma, manta, velocity and many others have post holes; one downside is they use grub screws which require an allen key to tighten; the allen key comes with the rda.
my 3d has no post holes; you wrap the coil leg round the screw head and screw in with a small commonplace regular screwdriver
7: 4post versus 3post
For dual coil, it's easier to have two independent spots to connect the positive legs of two different coils.