Well our system is different obviously, but I'm in the Holy Royal Arch, the Mark and the Royal Ark Mariners (an appendant body that's "moored" to each Mark lodge, so most people join both).
And why? Well the Mark fills in some of the gaps for the Fellowcraft and the Roya Arch completes the Master Mason's journey. The RAM? Well for the apron and collar of course 🤣
I was raised earlier this year. The consensus, I've gathered, is to focus on the Blue for at least a year to internalize the basics (and to avoid neglecting the home lodge in favor of a shiny new body). That said, I find the Scottish Rite interesting, and hope to explore it after I've solidified my footing in my home lodge. The Southern Jurisdiction offers an online learning space with a basic course "The Master's Steps" to reinforce Blue Lodge work. I've started it, and it's both deepened my appreciation for the work so far, and further kindled my curiosity for the Scottish Rite in general