>>35969832FRLG->Emerald->Platinum->HGSS->BW->BW2->XY
SM has better plot but USUM has fixes to the features introduced in SM, more Pokemon and better online support
There's no reason to play ORAS, it's an okish remake with less content than the original RSE and it isn't even plot relevant because different people wrote it and there's some alternate timeline shenanigand, if you do come to care for the plot.
There's also no reason to play RGB, GSC, RS and DP. RGB and GSC were remade into FRLG and HGSS, and Emerald and Platinum are the third enhanced versions of RS and DP.
