First of all, welcome to ECF jUsoNeaZn.
I started with a Blu kit, but it wasn't enough to get me off analogs. Then I got some cartos from a company called The Magic Mist, and they were a good step up from the Blu cartos - but still not quite good enough to make me leave behind the stink sticks.
Then I got my Halo G6 kit, and the day I received it was my last day of lighting up. Others here are much more knowledgeable than I, but from everything I've read, Halo is one of the best brands of cigalike* out there. The G6 rig was plenty good enough to get me off analogs in flavor, throat hit and nicotine delivery. Other brands I've seen a lot of positive comments on include V2, MigCigs and Green Smoke. But I suspect that you're not going to experience a significant improvement over your G6, at least in the hardware category.
Regarding e-liquids, you should be able to vape in your G6 just about any brand/flavor of juice out there, at least with a fairly neutral (50/50) ratio between two of the primary ingredients in e-liquids, PG (propylene glycol) and VG (vegetable glycerin). Many juice vendors advertise their PG/VG ratios on their websites (although Halo is one that doesn't), and some even let you select the ratio you like the best. The three brands I'm buying from over the next few weeks are going to be Mt. Baker Vapor, Ahlusion and Nicoticket. These brands are touted more often than most others on ECF.
Bottom line - I'd recommend sticking with your G6 unless/until you want to venture into the larger and more complex vaping devices. But go ahead and venture out for juices, and scan ECF to find some really good recommendations.
* -- "Cigalike" = vaping devices that at least somewhat resemble actual cigarettes.
P.S. - If you'd like a slightly warmer vape than you're getting with the standard Halo cartomizers, I'd recommend trying their "LR" (low resistance) blank cartomizers. Lower resistance allows more electrical current to be delivered, resulting in a warmer vape. I find Halo's regular cartos to be a bit too cool with most of the flavors I've tried. (Not to imply that everyone has the same taste preferences.)