You could use sport weight yarn. Both Louet Gems Opal (solids) and Claudia's Hand-Painted Sportweight are beautiful!
Lorna's Laces also makes a soft squishy sportweight, and Dream in Color's Smooshy is between a sport weight and fingering (plus DIC is dyed in the Chicago burbs!)
Another almost sport-weight is Colinette Jitterbug, which also has the yummiest colors!
Even though i'm linking them to canadian site, they're all available thru US sites. I'm just too lazy to look for them.