It is worth the effort to try again. I think most Brazilians would appreciate the game you're playing doing a mileage run. You'll do better face to face though.
I also wouldn't expect the same response at other consulates, they're all a bit different.
Bringing along a Brazlian always helps. My daughter is Brazilian, and they love hearing that.
5 year visas are the norm, and they are great. I'm going down wednesday for 3 nights on short notice, no problem.