Yes you shouldn't have too much trouble getting down to 1.4 ohms or so. Anything less than that and I think you wouldn't have enough surface area on the coil for a good vape.
Twisting the wire is also a good way to drop your coil resistance. Some people even prefer twisted thin-gauge wire over a thicker gauge wire, but that is something I avoid unless I had no thicker wire available.
If your RBA allows for it, a dual coil build will also lower your resistance. If you build two 2.0 ohm coils, together they will give you an overall resistance of 1.0 ohms. This may sound counterintuitive if you don't have any previous experience with electronics, but it's the way things work.
So you have a few options to try while you wait for your (soon to be made) order for 28 gauge Kanthal to be delivered.
