First sequence I start with is usually the hook/chorus/drop. I'll usually copy that and make variations to bring into the song later. I also typically work on a verse-like track, as well as some quick and easy intro and outro bars. There's usually another random 1 or 2 sequences that kinda come about in the process as well and I'll try to fit them in as transitions/bridges/builds/etc, otherwise I'll throw some of those together if necessary . And maybe if I've been working on that hook, main part, whatever...and it's 8 bars, well then I copy it 4 times and work with each a little bit differently so I can throw them together for 32 bars. Maybe I don't need 4 copies of that hook, maybe I can repeat the same pattern 3 times and only have to create one additional copy to tack on the end with the fills/breaks/etc. Are my sequences all that complicated? No. A lot of time it's just adding something like a snare, then some hats, then a bassline...nothing that can't be done with track mutes in a single sequence. It's not about how many sequences you have, it's how you get what you have to flow. So just do what works for you, man. If you can get a song done with one sequence and can do it comfortably, there's no reason to change that.
MPC 1000 w/jjOS, Elektron Octratrack, Korg EX-8000 & MS-20 Mini, Behringer Neutron, E-mu E6400 Ultra, circuit bent Roland TR 505, Mackie 1604 VLZ3, Electrix Filter Factory, delays & compressors