Roserade is more overwhelming than Deoxys D or Froslass. Roserade also has Toxic Spikes and has Sleep Powder when using a set without Spikes. Roserade also utilizes a LO set with Leaf Storm/Sludge Bomb which 2hkoes everything bar Steel types and Snorlax (and maybe Deoxys D/Cress which get Sleep Powdered anyway). Right now, the metagame is based around Spikes and Spin blocking. Roserade is the no.1 culprit for Spikes.
Also, I don't see a problem with suspecting all three. Roserade should go BL by itself and then Deoxys-D and Froslass should be suspected afterwards.
Also, I don't see a problem with suspecting all three. Roserade should go BL by itself and then Deoxys-D and Froslass should be suspected afterwards.