For ease of build, I'd recommend any 4 hole design. The Plume Veil is an awesome atty. I've built it with single, dual, and most recently quad
coils. For a great dual coil only set up, the Infinite CLT makes for a great atty. though duals and quads are all you can run in it. I've never played with a Helios, but that was one of the first 4 hole designs that came out. And the Helios clones are pretty cheap.
I love my Magma. But it is not my most versatile atty. For single or dual
coils, it give crazy great flavor. But as a cloud chaser, it will under perform when compared to others.