For anyone interested, the Peakmonsters family of guilds has some spots open for players wanting to get involved with brawls. There are currently 9 guilds flying the PM flag and 6 of these are competitive and only are accepting top tier players with proven track records. There are another 3 'Feeder' guilds where newer players can apply and work their way up into the competitive guilds over time if they prove themselves. The PeakD discord channel is the best place to apply or contact someone for more information.
Pogs is absolutely right about the brawls, there are plans for additional SPS rewards in the brawls later this year as well so getting started now gets you a running start when those rewards are possible.