Tony and Hilary's 3 in 1 Studio: Sofa with low book cases at each end. This arrangement adds shelf storage without taking up wall space and provides narrow end table surfaces at each end of the sofa. Side chairs are streamlined, not bulky.
Ron's Hotel "Sweet": Sofa with upholstered side stools. The stools are backless and a lot less cumbersome than side chairs. They create extra seating next to the sofa without blocking off light and space with backs or arms.
David & Im's OneSpace: Sofa against dining table. The partial-backed sofa right up against the dining table provides seating that can face the dining or living area.
Kevin's Triple Threat: A sleeper sofa provides David's small studio space with guest bedroom, living, and dining seating all-in-one.
Brenden & Shannon's Charm & Character: A rug and nice, full-sized (yet low-profile), carefully-selected furnishings carve out a comfy living room seating arrangement that looks like it could be from a much larger home.
Laura's Small & Snug: Despite being in a studio, two sofas provide lots of comfy seating in a "living room" defined by a rug. They don't feel cramped at all, so small space does not necessarily = small furniture. Sometimes a couple large pieces can be more appropriate than lots of small ones.
emilyjoyce's Separate Spaces: When tiny means no room for a sofa, don't give up on a seating arrangement altogether. Here, two matching armchairs and a glass coffee table sit opposite the bed. The glass of the coffee table has a minimum visual impact and the armed seats are diminutive yet comfortable.
Nathan Andrew's Serene & Masculine: A roomy custom daybed doubles as sofa and bed in this studio. Storage at the arms provides end tables and a slim coffee table saves space. Clutter is reduced on the side table surfaces with wall-mounted lamps.