The honor system doesn't fully depend on how much honor you get (but which is nice to consider in this system), but how much AVERAGE honor you get.
So that means if you get 20-30 honor spread out through multiple games, at least 1-3 honors, your average is mid-high, since you're getting a lot of honors in a larger window of time. But if your friends are nailing much more honor in a shorter time, maybe 2-4, more consistently, their average will be much higher, and thus will need less progress to reach the next level.
This is funnily the same exact scenario as me and my girl (Mistress Nyx), where I got level 3 honor a lot faster than she did even though we pretty much constantly duo q'd and stopped playing altogether if one of us left. I ended up sometimes getting all honors on the team (4 of them), but ended up averaging on 2-3 per game consistently, but then she sometimes nailed all 4 every 3-4 games, and no less. While she might be getting more honor than I have constantly, she's taken a little longer to progress since it isn't as frequent.
Of course, this isn't a fail-proof way to see the system, since it can change, and might be wrong, but it's close.
