In response to the "offensive bias" that I have also noticed rather quickly, I threw together an anti-meta team. This team consists of Rotom-H, Mandibuzz, Sableye, Dugtrio, Tentacruel and Toxic Orb Breloom.
This team is incredibly effective on a ladder, and thus is a testament to how stale many OU teams are nowadays. I'll break it down:
Def Rotom-H for Genesect, Talonflame, Mamoswine and SR leads that do not like getting burned. Also checks Thundurus (T/I), Landorus (T/I)
SDef Mandibuzz for Aegislash, Specs Latios, Landorus and almost any other powerful special attacker. Also Defog support.
Sableye for Kangaskhan and many other notable physical attackers.
Dugtrio for Heatran, Excadrill, Tyranitar, (Mega) Lucario and revenge killing with an intact sash.
SDef Toxic Orb Breloom for Rotom-W, slow setup sweepers, Chansey, Blissey, miscellaneous shenanigans. Surprisingly effective again heavy offense once it sets up a free sub against the Rotom-W that is on literally every team.
Def Tentacruel for Azumarill, Keldeo, checks Lucario and covers the rest of the team's weaknesses.
A team like this should NOT get me something like a 50-15 ratio on the Pokebank ladder. The current metagame and cookie-cutter offensive teams just beg for a rise in anti-meta threats. With permanent weather removed, the ability to design anti-meta teams is easier than ever.