Should I install steam/origin on SSD and map some games to HDD or other way around?

Steam/Origin programs themselves are small, but may make many changes to there own directories, because of this I won't install them on the SSD.

Personally I'd map specific directories only; i.e

/dir/steam/steamapps/common/game1/ maps to SSD:/game1/

This way you get full performance from the SSD without having to mess with Steam/Orgin's settings.

Also I'd ONLY map games that have large loads, small games aren't going to give a large enough difference in load speed.

NOTE: The only time I'd install Steam/Orgin on the SSD would be if there were only say 1 or 2 games installed and I wanted performance from both, then instead of hassling with mapping directories I'd just install all on the same drive.