I have a couple small wave boards that I really like. First off I have a 5'10 Airglide by Y "Tom Morey" the guys at Catch Surf make them. It works really well in small mushy conditions. It gets flying down the line and is good for small airs and skate style surfing. If the waves are really small or breaking onto the shore, get yourself a Beater board finless or twin fin. They are super fun as well.
Finally, my other small wave board is a 6'1 JS Industries Blak Box. I used it for the first time the other day in waist to chest surf at a rocky point break in NH. These waves were a little quicker and steeper. They were perfect for this board. It was ripping sharp turns and was really easy to break the fins loose and throw some water. Look into these boards... they are worth it!
I'll log it during certain conditions, but I picked up a 5'8" Fishcuit and have had a blast riding that in all sorts of small waves - punchy, weak, flattish. No reason shortboards and longboards can't coexist in waves of all sizes and characteristics.